From cc55a380f64fd6bf99d84209df5305f35cfc4629 Mon Sep 17 00:00:00 2001
From: Jerico <jtsanchez9@up.edu.ph>
Date: Mon, 30 Jun 2025 22:32:37 +0800
Subject: [PATCH 01/20] Issue #2106 - Part 1: Un-prefix -moz-user-select

---
 layout/style/nsCSSPropList.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/layout/style/nsCSSPropList.h b/layout/style/nsCSSPropList.h
index 4367dd1e1e..8b012dbf37 100644
--- a/layout/style/nsCSSPropList.h
+++ b/layout/style/nsCSSPropList.h
@@ -4391,9 +4391,9 @@ CSS_PROP_USERINTERFACE(
     CSS_PROP_NO_OFFSET,
     eStyleAnimType_Discrete) // XXX bug 3935
 CSS_PROP_UIRESET(
-    -moz-user-select,
+    user-select,
     user_select,
-    CSS_PROP_DOMPROP_PREFIXED(UserSelect),
+    UserSelect,
     CSS_PROPERTY_PARSE_VALUE,
     "",
     VARIANT_HK,

From 17b594b705c3d824ba04e223d4946149540bc763 Mon Sep 17 00:00:00 2001
From: Jerico <jtsanchez9@up.edu.ph>
Date: Mon, 30 Jun 2025 22:32:54 +0800
Subject: [PATCH 02/20] Issue #2106 - Part 2: Align value names

---
 toolkit/components/aboutmemory/content/aboutMemory.css | 10 +++++-----
 toolkit/content/minimal-xul.css                        |  4 ++--
 toolkit/content/xul.css                                |  4 ++--
 toolkit/mozapps/extensions/content/extensions.css      |  6 +++---
 toolkit/themes/shared/aboutReader.css                  |  2 +-
 toolkit/themes/shared/datetimeinputpickers.css         |  2 +-
 toolkit/themes/shared/in-content/common.inc.css        |  4 ++--
 toolkit/themes/shared/plugins/pluginProblem.css        |  2 +-
 8 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/toolkit/components/aboutmemory/content/aboutMemory.css b/toolkit/components/aboutmemory/content/aboutMemory.css
index cf4d36de87..c359857a40 100644
--- a/toolkit/components/aboutmemory/content/aboutMemory.css
+++ b/toolkit/components/aboutmemory/content/aboutMemory.css
@@ -16,7 +16,7 @@ body {
 
 div.ancillary {
   margin: 0.5em 0;
-  -moz-user-select: none;
+  user-select: none;
 }
 
 div.section {
@@ -71,7 +71,7 @@ h3 {
 a.upDownArrow {
   font-size: 130%;
   text-decoration: none;
-  -moz-user-select: none;  /* no need to include this when cutting+pasting */
+  user-select: none;  /* no need to include this when cutting+pasting */
 }
 
 .accuracyWarning {
@@ -114,17 +114,17 @@ a.upDownArrow {
 }
 
 .noselect {
-  -moz-user-select: none;  /* no need to include this when cutting+pasting */
+  user-select: none;  /* no need to include this when cutting+pasting */
 }
 
 .option {
   font-size: 80%;
-  -moz-user-select: none;  /* no need to include this when cutting+pasting */
+  user-select: none;  /* no need to include this when cutting+pasting */
 }
 
 .legend {
   font-size: 80%;
-  -moz-user-select: none;  /* no need to include this when cutting+pasting */
+  user-select: none;  /* no need to include this when cutting+pasting */
 }
 
 .debug {
diff --git a/toolkit/content/minimal-xul.css b/toolkit/content/minimal-xul.css
index 0cd41922d1..80526cc9ac 100644
--- a/toolkit/content/minimal-xul.css
+++ b/toolkit/content/minimal-xul.css
@@ -23,7 +23,7 @@
 
 * {
   -moz-user-focus: ignore;
-  -moz-user-select: none;
+  user-select: none;
   display: -moz-box;
   box-sizing: border-box;
 }
@@ -97,7 +97,7 @@ thumb {
 }
 
 scrollbar, scrollbarbutton, scrollcorner, slider, thumb, scale {
-  -moz-user-select: none;
+  user-select: none;
 }
 
 scrollcorner {
diff --git a/toolkit/content/xul.css b/toolkit/content/xul.css
index 0aa0d3a217..9d94df64c0 100644
--- a/toolkit/content/xul.css
+++ b/toolkit/content/xul.css
@@ -658,7 +658,7 @@ treecol.treecol-image {
 tree > treechildren {
   display: -moz-box;
   -moz-binding: url("chrome://global/content/bindings/tree.xml#treebody");
-  -moz-user-select: none;
+  user-select: none;
   -moz-box-flex: 1;
 }
 
@@ -763,7 +763,7 @@ progressmeter {
 
 textbox {
   -moz-binding: url("chrome://global/content/bindings/textbox.xml#textbox");
-  -moz-user-select: text;
+  user-select: text;
   text-shadow: none;
 }
 
diff --git a/toolkit/mozapps/extensions/content/extensions.css b/toolkit/mozapps/extensions/content/extensions.css
index 3eeb173bde..c4c4e8ee1c 100644
--- a/toolkit/mozapps/extensions/content/extensions.css
+++ b/toolkit/mozapps/extensions/content/extensions.css
@@ -61,7 +61,7 @@ xhtml|link {
 
 .text-list {
   white-space: pre-line;
-  -moz-user-select: element;
+  user-select: contain;
 }
 
 setting, row[unsupported="true"] {
@@ -203,10 +203,10 @@ setting[type="menulist"] {
 }
 
 .addon .relnotes {
-  -moz-user-select: text;
+  user-select: text;
 }
 #detail-name, #detail-desc, #detail-fulldesc {
-  -moz-user-select: text;
+  user-select: text;
 }
 
 /* Make sure we're not animating hidden images. See bug 623739. */
diff --git a/toolkit/themes/shared/aboutReader.css b/toolkit/themes/shared/aboutReader.css
index 1bfbd0309d..831fd31d24 100644
--- a/toolkit/themes/shared/aboutReader.css
+++ b/toolkit/themes/shared/aboutReader.css
@@ -216,7 +216,7 @@ body:not(.loaded) .toolbar:-moz-locale-dir(rtl) {
   padding: 0;
   list-style: none;
   background-color: #fbfbfb;
-  -moz-user-select: none;
+  user-select: none;
   border-right: 1px solid #b5b5b5;
   z-index: 1;
 }
diff --git a/toolkit/themes/shared/datetimeinputpickers.css b/toolkit/themes/shared/datetimeinputpickers.css
index f0c4315e5b..05f4ad2e77 100644
--- a/toolkit/themes/shared/datetimeinputpickers.css
+++ b/toolkit/themes/shared/datetimeinputpickers.css
@@ -315,7 +315,7 @@ button.month-year.active::after {
   padding: calc((var(--spinner-item-height) - var(--font-size-default)) / 2) 0;
   margin-bottom: var(--spinner-item-margin-bottom);
   height: var(--spinner-item-height);
-  -moz-user-select: none;
+  user-select: none;
   scroll-snap-coordinate: 0 0;
 }
 
diff --git a/toolkit/themes/shared/in-content/common.inc.css b/toolkit/themes/shared/in-content/common.inc.css
index ecd961d8da..a34f36bd6f 100644
--- a/toolkit/themes/shared/in-content/common.inc.css
+++ b/toolkit/themes/shared/in-content/common.inc.css
@@ -655,7 +655,7 @@ xul|*.radio-label-box {
   padding-bottom: 2px;
   padding-inline-start: 9px;
   margin: 0;
-  -moz-user-select: none;
+  user-select: none;
 }
 
 *|*.category-icon {
@@ -678,7 +678,7 @@ xul|*.radio-label-box {
   font-weight: normal;
   line-height: 40px;
   margin: 0;
-  -moz-user-select: none;
+  user-select: none;
 }
 
 /* File fields */
diff --git a/toolkit/themes/shared/plugins/pluginProblem.css b/toolkit/themes/shared/plugins/pluginProblem.css
index 9929bd92aa..9e40456d45 100644
--- a/toolkit/themes/shared/plugins/pluginProblem.css
+++ b/toolkit/themes/shared/plugins/pluginProblem.css
@@ -15,7 +15,7 @@
   height: 100%;
   background-color: rgb(72,72,72);
   color: white;
-  -moz-user-select: none;
+  user-select: none;
 }
 
 .hoverBox {

From 552cb8dbccca0d735d1a0339c5d9beb7a57a7aa2 Mon Sep 17 00:00:00 2001
From: Francis Dominic Fajardo <fofajardo@up.edu.ph>
Date: Fri, 20 Jun 2025 10:33:02 +0800
Subject: [PATCH 03/20] No issue - Fix mixing of tabs with space-indented code.

---
 layout/style/nsRuleNode.cpp | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/layout/style/nsRuleNode.cpp b/layout/style/nsRuleNode.cpp
index 21af533726..152fb01b2f 100644
--- a/layout/style/nsRuleNode.cpp
+++ b/layout/style/nsRuleNode.cpp
@@ -2938,7 +2938,7 @@ nsRuleNode::SetDefaultOnRoot(const nsStyleStructID aSID, nsStyleContext* aContex
       }                                                                       \
     } else {                                                                  \
       data_ = new (mPresContext) nsStyle##type_(mPresContext);                \
-    }	                                                                      \
+    }                                                                         \
   }                                                                           \
                                                                               \
   if (!parentdata_) {                                                         \
@@ -3313,7 +3313,7 @@ nsRuleNode::FindNextSmallerFontSize(nscoord aFontSize, int32_t aBasePointSize,
         indexFontSize = CalcFontPointSize(index, aBasePointSize, aPresContext, aFontSizeType);
         if (indexFontSize < aFontSize) {
           break;
-	}
+        }
       }
       // set up points beyond table for interpolation purposes
       if (indexFontSize == smallestIndexFontSize) {
@@ -3379,7 +3379,7 @@ nsRuleNode::FindNextLargerFontSize(nscoord aFontSize, int32_t aBasePointSize,
         indexFontSize = CalcFontPointSize(index, aBasePointSize, aPresContext, aFontSizeType);
         if (indexFontSize > aFontSize) {
           break;
-	}
+        }
       }
       // set up points beyond table for interpolation purposes
       if (indexFontSize == smallestIndexFontSize) {
@@ -7843,7 +7843,7 @@ nsRuleNode::ComputeBorderData(void* aStartStruct,
         if (SetColor(list->mValue, unused, mPresContext,
                      aContext, borderColor, conditions)) {
           border->AppendBorderColor(side, borderColor);
-	} else {
+        } else {
           NS_NOTREACHED("unexpected item in -moz-border-*-colors list");
         }
         list = list->mNext;
@@ -10725,12 +10725,12 @@ nsRuleNode::HasAuthorSpecifiedRules(nsStyleContext* aStyleContext,
       for (uint32_t i = 0; i < nValues; ++i) {
         if (values[i]->GetUnit() == eCSSUnit_Null) {
           values[i]->SetDummyValue();
-	}
+        }
       }
       for (uint32_t i = 0; i < nValues; ++i) {
         if (values[i]->GetUnit() == eCSSUnit_DummyInherit) {
           values[i]->Reset();
-	}
+        }
       }
       styleContext = styleContext->GetParent();
     }

From dd2cf17d30b47fbbeb0505cded5a2d778f5c1e3e Mon Sep 17 00:00:00 2001
From: Francis Dominic Fajardo <fofajardo@up.edu.ph>
Date: Fri, 20 Jun 2025 10:33:13 +0800
Subject: [PATCH 04/20] Issue #2045 - Part 1: Revert "Temporarily force hidden
 elements to be actually hidden."

This reverts commit 1692fa52914012b051484c51caaed8e227334558.
---
 layout/style/res/html.css | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/layout/style/res/html.css b/layout/style/res/html.css
index 7a6d67f66f..53c88cbdc5 100644
--- a/layout/style/res/html.css
+++ b/layout/style/res/html.css
@@ -720,12 +720,12 @@ canvas {
 /* hidden elements */
 base, basefont, datalist, head, meta, script, style, title,
 noembed, param, template {
-   display: none !important;
+   display: none;
 }
 
 area {
   /* Don't give it frames other than its imageframe */
-  display: none !important;
+  display: none ! important;
 }
 
 iframe:fullscreen {

From 7f3f90eed4fe4ce4c8953b224a346cbc69e93674 Mon Sep 17 00:00:00 2001
From: Francis Dominic Fajardo <fofajardo@up.edu.ph>
Date: Fri, 20 Jun 2025 10:33:22 +0800
Subject: [PATCH 05/20] Issue #2045 - Part 2: Add handling and storage for the
 revert unit and value

---
 layout/style/nsCSSValue.cpp | 52 ++++++++++++++++++++++++++++++++-----
 layout/style/nsCSSValue.h   | 10 +++++++
 2 files changed, 55 insertions(+), 7 deletions(-)

diff --git a/layout/style/nsCSSValue.cpp b/layout/style/nsCSSValue.cpp
index 6553ebaf33..24e804d800 100644
--- a/layout/style/nsCSSValue.cpp
+++ b/layout/style/nsCSSValue.cpp
@@ -166,6 +166,9 @@ nsCSSValue::nsCSSValue(const nsCSSValue& aCopy)
     mValue.mComplexColor = aCopy.mValue.mComplexColor;
     mValue.mComplexColor->AddRef();
   }
+  else if (eCSSUnit_Revert == mUnit) {
+    mValue.mCascadeOrigin = aCopy.mValue.mCascadeOrigin;
+  }
   else if (UnitHasArrayValue()) {
     mValue.mArray = aCopy.mValue.mArray;
     mValue.mArray->AddRef();
@@ -279,6 +282,9 @@ bool nsCSSValue::operator==(const nsCSSValue& aOther) const
     else if (eCSSUnit_ComplexColor == mUnit) {
       return *mValue.mComplexColor == *aOther.mValue.mComplexColor;
     }
+    else if (eCSSUnit_Revert == mUnit) {
+      return mValue.mCascadeOrigin == aOther.mValue.mCascadeOrigin;
+    }
     else if (UnitHasArrayValue()) {
       return *mValue.mArray == *aOther.mValue.mArray;
     }
@@ -539,6 +545,15 @@ nsCSSValue::SetComplexColorValue(already_AddRefed<ComplexColorValue> aValue)
   mValue.mComplexColor = aValue.take();
 }
 
+void
+nsCSSValue::SetCascadeOriginValue(mozilla::SheetType aValue, nsCSSUnit aUnit)
+{
+  MOZ_ASSERT(aUnit == eCSSUnit_Revert, "bad unit");
+  Reset();
+  mUnit = aUnit;
+  mValue.mCascadeOrigin = aValue;
+}
+
 void nsCSSValue::SetArrayValue(nsCSSValue::Array* aValue, nsCSSUnit aUnit)
 {
   Reset();
@@ -598,7 +613,7 @@ void nsCSSValue::SetFontFamilyListValue(css::FontFamilyListRefCnt* aValue)
 
 void nsCSSValue::SetPairValue(const nsCSSValuePair* aValue)
 {
-  // pairs should not be used for null/inherit/initial values
+  // pairs should not be used for null/inherit/initial/unset/revert values
   MOZ_ASSERT(aValue &&
              aValue->mXValue.GetUnit() != eCSSUnit_Null &&
              aValue->mYValue.GetUnit() != eCSSUnit_Null &&
@@ -607,7 +622,9 @@ void nsCSSValue::SetPairValue(const nsCSSValuePair* aValue)
              aValue->mXValue.GetUnit() != eCSSUnit_Initial &&
              aValue->mYValue.GetUnit() != eCSSUnit_Initial &&
              aValue->mXValue.GetUnit() != eCSSUnit_Unset &&
-             aValue->mYValue.GetUnit() != eCSSUnit_Unset,
+             aValue->mYValue.GetUnit() != eCSSUnit_Unset &&
+             aValue->mXValue.GetUnit() != eCSSUnit_Revert &&
+             aValue->mYValue.GetUnit() != eCSSUnit_Revert,
              "missing or inappropriate pair value");
   Reset();
   mUnit = eCSSUnit_Pair;
@@ -625,7 +642,9 @@ void nsCSSValue::SetPairValue(const nsCSSValue& xValue,
              xValue.GetUnit() != eCSSUnit_Initial &&
              yValue.GetUnit() != eCSSUnit_Initial &&
              xValue.GetUnit() != eCSSUnit_Unset &&
-             yValue.GetUnit() != eCSSUnit_Unset,
+             yValue.GetUnit() != eCSSUnit_Unset &&
+             xValue.GetUnit() != eCSSUnit_Revert &&
+             yValue.GetUnit() != eCSSUnit_Revert,
              "inappropriate pair value");
   Reset();
   mUnit = eCSSUnit_Pair;
@@ -635,7 +654,7 @@ void nsCSSValue::SetPairValue(const nsCSSValue& xValue,
 
 void nsCSSValue::SetTripletValue(const nsCSSValueTriplet* aValue)
 {
-  // triplet should not be used for null/inherit/initial values
+  // triplet should not be used for null/inherit/initial/unset/revert values
   MOZ_ASSERT(aValue &&
              aValue->mXValue.GetUnit() != eCSSUnit_Null &&
              aValue->mYValue.GetUnit() != eCSSUnit_Null &&
@@ -648,7 +667,10 @@ void nsCSSValue::SetTripletValue(const nsCSSValueTriplet* aValue)
              aValue->mZValue.GetUnit() != eCSSUnit_Initial &&
              aValue->mXValue.GetUnit() != eCSSUnit_Unset &&
              aValue->mYValue.GetUnit() != eCSSUnit_Unset &&
-             aValue->mZValue.GetUnit() != eCSSUnit_Unset,
+             aValue->mZValue.GetUnit() != eCSSUnit_Unset &&
+             aValue->mXValue.GetUnit() != eCSSUnit_Revert &&
+             aValue->mYValue.GetUnit() != eCSSUnit_Revert &&
+             aValue->mZValue.GetUnit() != eCSSUnit_Revert,
              "missing or inappropriate triplet value");
   Reset();
   mUnit = eCSSUnit_Triplet;
@@ -671,7 +693,10 @@ void nsCSSValue::SetTripletValue(const nsCSSValue& xValue,
              zValue.GetUnit() != eCSSUnit_Initial &&
              xValue.GetUnit() != eCSSUnit_Unset &&
              yValue.GetUnit() != eCSSUnit_Unset &&
-             zValue.GetUnit() != eCSSUnit_Unset,
+             zValue.GetUnit() != eCSSUnit_Unset &&
+             xValue.GetUnit() != eCSSUnit_Revert &&
+             yValue.GetUnit() != eCSSUnit_Revert &&
+             zValue.GetUnit() != eCSSUnit_Revert,
              "inappropriate triplet value");
   Reset();
   mUnit = eCSSUnit_Triplet;
@@ -781,6 +806,12 @@ void nsCSSValue::SetUnsetValue()
   mUnit = eCSSUnit_Unset;
 }
 
+void
+nsCSSValue::SetRevertValue(mozilla::SheetType aValue)
+{
+  SetCascadeOriginValue(aValue, eCSSUnit_Revert);
+}
+
 void nsCSSValue::SetNoneValue()
 {
   Reset();
@@ -1930,6 +1961,7 @@ nsCSSValue::AppendToString(nsCSSPropertyID aProperty, nsAString& aResult,
     case eCSSUnit_Inherit:      aResult.AppendLiteral("inherit");  break;
     case eCSSUnit_Initial:      aResult.AppendLiteral("initial");  break;
     case eCSSUnit_Unset:        aResult.AppendLiteral("unset");    break;
+    case eCSSUnit_Revert:       aResult.AppendLiteral("revert");   break;
     case eCSSUnit_None:         aResult.AppendLiteral("none");     break;
     case eCSSUnit_Normal:       aResult.AppendLiteral("normal");   break;
     case eCSSUnit_System_Font:  aResult.AppendLiteral("-moz-use-system-font"); break;
@@ -2189,6 +2221,10 @@ nsCSSValue::SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const
       n += mValue.mComplexColor->SizeOfIncludingThis(aMallocSizeOf);
       break;
 
+    // Cascade Origin: nothing extra to measure.
+    case eCSSUnit_Revert:
+      break;
+
     // Float: nothing extra to measure.
     case eCSSUnit_Percent:
     case eCSSUnit_Number:
@@ -2511,7 +2547,8 @@ nsCSSRect::AppendToString(nsCSSPropertyID aProperty, nsAString& aResult,
   MOZ_ASSERT(mTop.GetUnit() != eCSSUnit_Null &&
              mTop.GetUnit() != eCSSUnit_Inherit &&
              mTop.GetUnit() != eCSSUnit_Initial &&
-             mTop.GetUnit() != eCSSUnit_Unset,
+             mTop.GetUnit() != eCSSUnit_Unset &&
+             mTop.GetUnit() != eCSSUnit_Revert,
              "parser should have used a bare value");
 
   if (eCSSProperty_border_image_slice == aProperty ||
@@ -2681,6 +2718,7 @@ nsCSSValuePairList::AppendToString(nsCSSPropertyID aProperty,
     if (item->mXValue.GetUnit() != eCSSUnit_Inherit &&
         item->mXValue.GetUnit() != eCSSUnit_Initial &&
         item->mXValue.GetUnit() != eCSSUnit_Unset &&
+        item->mXValue.GetUnit() != eCSSUnit_Revert &&
         item->mYValue.GetUnit() != eCSSUnit_Null) {
       aResult.Append(char16_t(' '));
       item->mYValue.AppendToString(aProperty, aResult, aSerialization);
diff --git a/layout/style/nsCSSValue.h b/layout/style/nsCSSValue.h
index 7d0556046b..680e26732a 100644
--- a/layout/style/nsCSSValue.h
+++ b/layout/style/nsCSSValue.h
@@ -484,6 +484,7 @@ enum nsCSSUnit {
   eCSSUnit_TokenStream  = 43,     // (nsCSSValueTokenStream*) value
   eCSSUnit_GridTemplateAreas   = 44,   // (GridTemplateAreasValue*)
                                        // for grid-template-areas
+  eCSSUnit_Revert       = 45,     // (SheetType) value is the current cascade origin
 
   eCSSUnit_Pair         = 50,     // (nsCSSValuePair*) pair of values
   eCSSUnit_Triplet      = 51,     // (nsCSSValueTriplet*) triplet of values
@@ -911,6 +912,12 @@ public:
     return mValue.mFloatColor;
   }
 
+  mozilla::SheetType GetCascadeOriginValue() const
+  {
+    MOZ_ASSERT(mUnit == eCSSUnit_Revert, "not a cascade origin value");
+    return mValue.mCascadeOrigin;
+  }
+
   void Reset()  // sets to null
   {
     if (mUnit != eCSSUnit_Null)
@@ -943,6 +950,7 @@ public:
   void SetRGBAColorValue(const mozilla::css::RGBAColorData& aValue);
   void SetComplexColorValue(
     already_AddRefed<mozilla::css::ComplexColorValue> aValue);
+  void SetCascadeOriginValue(mozilla::SheetType aValue, nsCSSUnit aUnit);
   void SetArrayValue(nsCSSValue::Array* aArray, nsCSSUnit aUnit);
   void SetURLValue(mozilla::css::URLValue* aURI);
   void SetImageValue(mozilla::css::ImageValue* aImage);
@@ -961,6 +969,7 @@ public:
   void SetInheritValue();
   void SetInitialValue();
   void SetUnsetValue();
+  void SetRevertValue(mozilla::SheetType aValue);
   void SetNoneValue();
   void SetAllValue();
   void SetNormalValue();
@@ -1054,6 +1063,7 @@ protected:
     nsCSSValueFloatColor* MOZ_OWNING_REF mFloatColor;
     mozilla::css::FontFamilyListRefCnt* MOZ_OWNING_REF mFontFamilyList;
     mozilla::css::ComplexColorValue* MOZ_OWNING_REF mComplexColor;
+    mozilla::SheetType mCascadeOrigin;
   } mValue;
 };
 

From b0f09723145adfadef5ea3a94adc4e6396365312 Mon Sep 17 00:00:00 2001
From: Francis Dominic Fajardo <fofajardo@up.edu.ph>
Date: Thu, 3 Jul 2025 17:13:32 +0800
Subject: [PATCH 06/20] Issue #2045 - Part 3: Implement cascade origin tracking
 to CSS parser

The CSS parser already knows the cascade origin, but it is using a different enum for storing it.
---
 layout/style/nsCSSParser.cpp | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/layout/style/nsCSSParser.cpp b/layout/style/nsCSSParser.cpp
index f9a2bc9f50..b33167af76 100644
--- a/layout/style/nsCSSParser.cpp
+++ b/layout/style/nsCSSParser.cpp
@@ -1525,6 +1525,9 @@ protected:
   // enum type be signed.
   css::SheetParsingMode mParsingMode : 3;
 
+  // Indicates the cascade origin of the sheet.
+  mozilla::SheetType mLevel;
+
   // True if we are in parsing rules for the chrome.
   bool mIsChrome : 1;
 
@@ -1656,6 +1659,7 @@ CSSParserImpl::CSSParserImpl()
     mHashlessColorQuirk(false),
     mUnitlessLengthQuirk(false),
     mParsingMode(css::eAuthorSheetFeatures),
+    mLevel(mozilla::SheetType::Doc),
     mIsChrome(false),
     mViewportUnitsEnabled(true),
     mHTMLMediaMode(false),
@@ -1799,6 +1803,22 @@ CSSParserImpl::ParseSheet(const nsAString& aInput,
   }
 
   mParsingMode = mSheet->ParsingMode();
+  switch (mParsingMode) {
+    case css::eAgentSheetFeatures:
+      mLevel = mozilla::SheetType::Agent;
+      break;
+
+    case css::eUserSheetFeatures:
+      mLevel = mozilla::SheetType::User;
+      break;
+
+    case css::eAuthorSheetFeatures:
+      mLevel = mozilla::SheetType::Doc;
+      break;
+
+    default:
+      MOZ_CRASH("impossible value for aType");
+  }
   mIsChrome = dom::IsChromeURI(aSheetURI);
   mReusableSheets = aReusableSheets;
 
@@ -1824,6 +1844,7 @@ CSSParserImpl::ParseSheet(const nsAString& aInput,
   ReleaseScanner();
 
   mParsingMode = css::eAuthorSheetFeatures;
+  mLevel = mozilla::SheetType::Doc;
   mIsChrome = false;
   mReusableSheets = nullptr;
 

From 9105c58a307ec9c25e4fc7547b9a9b9cd439e98b Mon Sep 17 00:00:00 2001
From: Francis Dominic Fajardo <fofajardo@up.edu.ph>
Date: Fri, 20 Jun 2025 10:33:30 +0800
Subject: [PATCH 07/20] Issue #2045 - Part 4: Parse "revert" in property values
 wherever "unset" is allowed

---
 dom/animation/TimingParams.cpp          |   1 +
 dom/canvas/CanvasRenderingContext2D.cpp |   1 +
 layout/style/FontFaceSet.cpp            |   2 +-
 layout/style/nsCSSKeywordList.h         |   1 +
 layout/style/nsCSSParser.cpp            | 173 +++++++++++++++---------
 layout/style/nsCSSProps.h               |   2 +-
 6 files changed, 113 insertions(+), 67 deletions(-)

diff --git a/dom/animation/TimingParams.cpp b/dom/animation/TimingParams.cpp
index f387f460f8..a020fd83af 100644
--- a/dom/animation/TimingParams.cpp
+++ b/dom/animation/TimingParams.cpp
@@ -154,6 +154,7 @@ TimingParams::ParseEasing(const nsAString& aEasing,
     case eCSSUnit_Inherit:
     case eCSSUnit_Initial:
     case eCSSUnit_Unset:
+    case eCSSUnit_Revert:
     case eCSSUnit_TokenStream:
     case eCSSUnit_Null:
       break;
diff --git a/dom/canvas/CanvasRenderingContext2D.cpp b/dom/canvas/CanvasRenderingContext2D.cpp
index 32241e7c98..e069312817 100644
--- a/dom/canvas/CanvasRenderingContext2D.cpp
+++ b/dom/canvas/CanvasRenderingContext2D.cpp
@@ -2731,6 +2731,7 @@ PropertyIsInheritOrInitial(Declaration* aDeclaration, const nsCSSPropertyID aPro
   const nsCSSValue* filterVal =
     aDeclaration->GetNormalBlock()->ValueFor(aProperty);
   return (!filterVal || (filterVal->GetUnit() == eCSSUnit_Unset ||
+                         filterVal->GetUnit() == eCSSUnit_Revert ||
                          filterVal->GetUnit() == eCSSUnit_Inherit ||
                          filterVal->GetUnit() == eCSSUnit_Initial));
 }
diff --git a/layout/style/FontFaceSet.cpp b/layout/style/FontFaceSet.cpp
index 04c04fd372..9b94e8af9b 100644
--- a/layout/style/FontFaceSet.cpp
+++ b/layout/style/FontFaceSet.cpp
@@ -201,7 +201,7 @@ FontFaceSet::ParseFontShorthandForMatching(
 
   const nsCSSValue* family = data->ValueFor(eCSSProperty_font_family);
   if (family->GetUnit() != eCSSUnit_FontFamilyList) {
-    // We got inherit, initial, unset, a system font, or a token stream.
+    // We got inherit, initial, unset, revert, a system font, or a token stream.
     aRv.Throw(NS_ERROR_DOM_SYNTAX_ERR);
     return;
   }
diff --git a/layout/style/nsCSSKeywordList.h b/layout/style/nsCSSKeywordList.h
index 033ca5db17..d389f4fe35 100644
--- a/layout/style/nsCSSKeywordList.h
+++ b/layout/style/nsCSSKeywordList.h
@@ -474,6 +474,7 @@ CSS_KEY(repeat, repeat)
 CSS_KEY(repeat-x, repeat_x)
 CSS_KEY(repeat-y, repeat_y)
 CSS_KEY(reverse, reverse)
+CSS_KEY(revert, revert)
 CSS_KEY(ridge, ridge)
 CSS_KEY(right, right)
 CSS_KEY(rl, rl)
diff --git a/layout/style/nsCSSParser.cpp b/layout/style/nsCSSParser.cpp
index b33167af76..e8078eaf9d 100644
--- a/layout/style/nsCSSParser.cpp
+++ b/layout/style/nsCSSParser.cpp
@@ -1170,8 +1170,9 @@ protected:
                                 nsString& aValue);
 
   /**
-   * Parses a CSS variable value.  This could be 'initial', 'inherit', 'unset'
-   * or a token stream, which may or may not include variable references.
+   * Parses a CSS variable value.  This could be 'initial', 'inherit', 'unset',
+   * 'revert', or a token stream, which may or may not include variable
+   * references.
    *
    * @param aType Out parameter into which the type of the variable value
    *   will be stored.
@@ -8206,6 +8207,10 @@ CSSParserImpl::ParseVariant(nsCSSValue& aValue,
           aValue.SetUnsetValue();
           return CSSParseResult::Ok;
         }
+        else if (eCSSKeyword_revert == keyword) {
+          aValue.SetRevertValue(mLevel);
+          return CSSParseResult::Ok;
+        }
       }
       if ((aVariantMask & VARIANT_NONE) != 0) {
         if (eCSSKeyword_none == keyword) {
@@ -8405,7 +8410,8 @@ CSSParserImpl::ParseVariant(nsCSSValue& aValue,
        !(tk->mIdent.LowerCaseEqualsLiteral("inherit") ||
          tk->mIdent.LowerCaseEqualsLiteral("initial") ||
          (tk->mIdent.LowerCaseEqualsLiteral("unset") &&
-          nsLayoutUtils::UnsetValueEnabled())))) {
+          nsLayoutUtils::UnsetValueEnabled()) ||
+         tk->mIdent.LowerCaseEqualsLiteral("revert")))) {
     aValue.SetStringValue(tk->mIdent, eCSSUnit_Ident);
     return CSSParseResult::Ok;
   }
@@ -8475,6 +8481,7 @@ CSSParserImpl::ParseCustomIdent(nsCSSValue& aValue,
   if (keyword == eCSSKeyword_inherit ||
       keyword == eCSSKeyword_initial ||
       keyword == eCSSKeyword_unset ||
+      keyword == eCSSKeyword_revert ||
       keyword == eCSSKeyword_default ||
       (aPropertyKTable &&
         nsCSSProps::FindIndexOfKeyword(keyword, aPropertyKTable) >= 0)) {
@@ -8696,7 +8703,7 @@ bool
 CSSParserImpl::ParseImageOrientation(nsCSSValue& aValue)
 {
   if (ParseSingleTokenVariant(aValue, VARIANT_INHERIT, nullptr)) {
-    // 'inherit', 'initial' and 'unset' must be alone
+    // 'inherit', 'initial', 'unset', and 'revert' must be alone
     return true;
   }
 
@@ -8810,7 +8817,7 @@ CSSParserImpl::ParseElement(nsCSSValue& aValue)
 bool
 CSSParserImpl::ParseFlex()
 {
-  // First check for inherit / initial / unset
+  // First check for inherit / initial / unset / revert
   nsCSSValue tmpVal;
   if (ParseSingleTokenVariant(tmpVal, VARIANT_INHERIT, nullptr)) {
     AppendValue(eCSSProperty_flex_grow, tmpVal);
@@ -10318,7 +10325,8 @@ bool
 CSSParserImpl::ParseInitialLetter()
 {
   nsCSSValue value;
-  // 'inherit', 'initial', 'unset', 'none', and 'normal' must be alone
+  // 'inherit', 'initial', 'unset', 'revert', 'none', and 'normal'
+  // must be alone
   if (!ParseSingleTokenVariant(value, VARIANT_INHERIT | VARIANT_NORMAL,
                                nullptr)) {
     nsCSSValue first, second;
@@ -11572,8 +11580,14 @@ CSSParserImpl::ParseChoice(nsCSSValue aValues[],
         }
         found = ((1 << aNumIDs) - 1);
       }
+      else if (eCSSUnit_Revert == aValues[0].GetUnit()) { // one revert, all revert
+        for (loop = 1; loop < aNumIDs; loop++) {
+          aValues[loop].SetRevertValue(mLevel);
+        }
+        found = ((1 << aNumIDs) - 1);
+      }
     }
-    else {  // more than one value, verify no inherits, initials or unsets
+    else {  // more than one value, verify no inherits, initials, unsets, or reverts
       for (loop = 0; loop < aNumIDs; loop++) {
         if (eCSSUnit_Inherit == aValues[loop].GetUnit()) {
           found = -1;
@@ -11587,6 +11601,10 @@ CSSParserImpl::ParseChoice(nsCSSValue aValues[],
           found = -1;
           break;
         }
+        else if (eCSSUnit_Revert == aValues[loop].GetUnit()) {
+          found = -1;
+          break;
+        }
       }
     }
   }
@@ -11625,12 +11643,13 @@ CSSParserImpl::ParseBoxProperties(const nsCSSPropertyID aPropIDs[])
     return false;
   }
 
-  if (1 < count) { // verify no more than single inherit, initial or unset
+  if (1 < count) { // verify no more than single inherit, initial, unset, or revert
     NS_FOR_CSS_SIDES (index) {
       nsCSSUnit unit = (result.*(nsCSSRect::sides[index])).GetUnit();
       if (eCSSUnit_Inherit == unit ||
           eCSSUnit_Initial == unit ||
-          eCSSUnit_Unset == unit) {
+          eCSSUnit_Unset == unit ||
+          eCSSUnit_Revert == unit) {
         return false;
       }
     }
@@ -11734,10 +11753,11 @@ CSSParserImpl::ParseBoxCornerRadius(nsCSSPropertyID aPropID)
     return false;
   }
 
-  // optional second value (forbidden if first value is inherit/initial/unset)
+  // optional second value (forbidden if first value is inherit/initial/unset/revert)
   if (dimenX.GetUnit() != eCSSUnit_Inherit &&
       dimenX.GetUnit() != eCSSUnit_Initial &&
-      dimenX.GetUnit() != eCSSUnit_Unset) {
+      dimenX.GetUnit() != eCSSUnit_Unset &&
+      dimenX.GetUnit() != eCSSUnit_Revert) {
     if (ParseNonNegativeVariant(dimenY, VARIANT_LP | VARIANT_CALC, nullptr) ==
         CSSParseResult::Error) {
       return false;
@@ -11795,12 +11815,14 @@ CSSParserImpl::ParseBoxCornerRadiiInternals(nsCSSValue array[])
       return false;
   }
 
-  // if 'initial', 'inherit' or 'unset' was used, it must be the only value
+  // if 'initial', 'inherit', 'unset', or 'revert' was used, it
+  // must be the only value
   if (countX > 1 || countY > 0) {
     nsCSSUnit unit = dimenX.mTop.GetUnit();
     if (eCSSUnit_Inherit == unit ||
         eCSSUnit_Initial == unit ||
-        eCSSUnit_Unset == unit)
+        eCSSUnit_Unset == unit ||
+        eCSSUnit_Revert == unit)
       return false;
   }
 
@@ -12547,6 +12569,7 @@ CSSParserImpl::ParseFontDescriptorValue(nsCSSFontDesc aDescID,
             aValue.GetUnit() != eCSSUnit_Inherit &&
             aValue.GetUnit() != eCSSUnit_Initial &&
             aValue.GetUnit() != eCSSUnit_Unset &&
+            aValue.GetUnit() != eCSSUnit_Revert &&
             (aValue.GetUnit() != eCSSUnit_Enumerated ||
              (aValue.GetIntValue() != NS_STYLE_FONT_WEIGHT_BOLDER &&
               aValue.GetIntValue() != NS_STYLE_FONT_WEIGHT_LIGHTER)));
@@ -12611,7 +12634,7 @@ CSSParserImpl::ParseImageLayers(const nsCSSPropertyID aTable[])
   // background-color can only be set once, so it's not a list.
   nsCSSValue color;
 
-  // Check first for inherit/initial/unset.
+  // Check first for inherit/initial/unset/revert.
   if (ParseSingleTokenVariant(color, VARIANT_INHERIT, nullptr)) {
     // must be alone
     for (const nsCSSPropertyID* subprops =
@@ -12808,7 +12831,8 @@ CSSParserImpl::ParseImageLayersItem(
       int32_t dummy;
       if (keyword == eCSSKeyword_inherit ||
           keyword == eCSSKeyword_initial ||
-          keyword == eCSSKeyword_unset) {
+          keyword == eCSSKeyword_unset ||
+          keyword == eCSSKeyword_revert) {
         return false;
       } else if (keyword == eCSSKeyword_none) {
         if (haveImage)
@@ -12971,7 +12995,7 @@ CSSParserImpl::ParseImageLayersItem(
       if (haveColor)
         return false;
       haveColor = true;
-      // Note: This parses 'inherit', 'initial' and 'unset', but
+      // Note: This parses 'inherit', 'initial', 'unset', and 'revert', but
       // we've already checked for them, so it's ok.
       if (ParseSingleValueProperty(aState.mColor,
                                    aTable[nsStyleImageLayers::color]) !=
@@ -12995,7 +13019,7 @@ CSSParserImpl::ParseValueList(nsCSSPropertyID aPropID)
 {
   // aPropID is a single value prop-id
   nsCSSValue value;
-  // 'initial', 'inherit' and 'unset' stand alone, no list permitted.
+  // 'initial', 'inherit', 'unset', and 'revert' stand alone, no list permitted.
   if (!ParseSingleTokenVariant(value, VARIANT_INHERIT, nullptr)) {
     nsCSSValueList* item = value.SetListValue();
     for (;;) {
@@ -13018,7 +13042,7 @@ bool
 CSSParserImpl::ParseImageLayerRepeat(nsCSSPropertyID aPropID)
 {
   nsCSSValue value;
-  // 'initial', 'inherit' and 'unset' stand alone, no list permitted.
+  // 'initial', 'inherit', 'unset', and 'revert' stand alone, no list permitted.
   if (!ParseSingleTokenVariant(value, VARIANT_INHERIT, nullptr)) {
     nsCSSValuePair valuePair;
     if (!ParseImageLayerRepeatValues(valuePair)) {
@@ -13068,7 +13092,7 @@ CSSParserImpl::ParseImageLayerRepeatValues(nsCSSValuePair& aValue)
 bool
 CSSParserImpl::ParseImageLayerPosition(const nsCSSPropertyID aTable[])
 {
-  // 'initial', 'inherit' and 'unset' stand alone, no list permitted.
+  // 'initial', 'inherit', 'unset', and 'revert' stand alone, no list permitted.
   nsCSSValue position;
   if (ParseSingleTokenVariant(position, VARIANT_INHERIT, nullptr)) {
     AppendValue(aTable[nsStyleImageLayers::positionX], position);
@@ -13109,7 +13133,7 @@ bool
 CSSParserImpl::ParseImageLayerPositionCoord(nsCSSPropertyID aPropID, bool aIsHorizontal)
 {
   nsCSSValue value;
-  // 'initial', 'inherit' and 'unset' stand alone, no list permitted.
+  // 'initial', 'inherit', 'unset', and 'revert' stand alone, no list permitted.
   if (!ParseSingleTokenVariant(value, VARIANT_INHERIT, nullptr)) {
     nsCSSValue itemValue;
     if (!ParseImageLayerPositionCoordItem(itemValue, aIsHorizontal)) {
@@ -13144,8 +13168,8 @@ CSSParserImpl::ParseImageLayerPositionCoord(nsCSSPropertyID aPropID, bool aIsHor
  * like "top," "left center," etc.
  *
  * @param aOut The nsCSSValuePair in which to place the result.
- * @param aAcceptsInherit If true, 'inherit', 'initial' and 'unset' are
- *   legal values
+ * @param aAcceptsInherit If true, 'inherit', 'initial', 'unset', and 'revert'
+ *   are legal values
  * @param aAllowExplicitCenter If true, 'center' is a legal value
  * @return Whether or not the operation succeeded.
  */
@@ -13164,7 +13188,8 @@ bool CSSParserImpl::ParseBoxPositionValues(nsCSSValuePair &aOut,
   } else if (result == CSSParseResult::Ok) {
     if (eCSSUnit_Inherit == xValue.GetUnit() ||
         eCSSUnit_Initial == xValue.GetUnit() ||
-        eCSSUnit_Unset == xValue.GetUnit()) {  // both are inherit, initial or unset
+        eCSSUnit_Unset == xValue.GetUnit() ||
+        eCSSUnit_Revert == xValue.GetUnit()) {  // both are inherit, initial, unset, or revert
       yValue = xValue;
       return true;
     }
@@ -13578,7 +13603,7 @@ bool
 CSSParserImpl::ParseImageLayerSize(nsCSSPropertyID aPropID)
 {
   nsCSSValue value;
-  // 'initial', 'inherit' and 'unset' stand alone, no list permitted.
+  // 'initial', 'inherit', 'unset', and 'revert' stand alone, no list permitted.
   if (!ParseSingleTokenVariant(value, VARIANT_INHERIT, nullptr)) {
     nsCSSValuePair valuePair;
     if (!ParseImageLayerSizeValues(valuePair)) {
@@ -13606,8 +13631,8 @@ CSSParserImpl::ParseImageLayerSize(nsCSSPropertyID aPropID)
  * Parses two values that correspond to lengths for the background-size
  * property.  These can be one or two lengths (or the 'auto' keyword) or
  * percentages corresponding to the element's dimensions or the single keywords
- * 'contain' or 'cover'.  'initial', 'inherit' and 'unset' must be handled by
- * the caller if desired.
+ * 'contain' or 'cover'.  'initial', 'inherit', 'unset', and 'revert' must be
+ * handled by the caller if desired.
  *
  * @param aOut The nsCSSValuePair in which to place the result.
  * @return Whether or not the operation succeeded.
@@ -13705,8 +13730,8 @@ CSSParserImpl::ParseBorderImageSlice(bool aAcceptsInherit,
 
   if (aAcceptsInherit &&
       ParseSingleTokenVariant(value, VARIANT_INHERIT, nullptr)) {
-    // Keywords "inherit", "initial" and "unset" can not be mixed, so we
-    // are done.
+    // Keywords "inherit", "initial", "unset", and "revert" can not be
+    // mixed, so we are done.
     AppendValue(eCSSProperty_border_image_slice, value);
     return true;
   }
@@ -13756,8 +13781,8 @@ CSSParserImpl::ParseBorderImageWidth(bool aAcceptsInherit)
 
   if (aAcceptsInherit &&
       ParseSingleTokenVariant(value, VARIANT_INHERIT, nullptr)) {
-    // Keywords "inherit", "initial" and "unset" can not be mixed, so we
-    // are done.
+    // Keywords "inherit", "initial", "unset", and "revert" can not be
+    // mixed, so we are done.
     AppendValue(eCSSProperty_border_image_width, value);
     return true;
   }
@@ -13779,8 +13804,8 @@ CSSParserImpl::ParseBorderImageOutset(bool aAcceptsInherit)
 
   if (aAcceptsInherit &&
       ParseSingleTokenVariant(value, VARIANT_INHERIT, nullptr)) {
-    // Keywords "inherit", "initial" and "unset" can not be mixed, so we
-    // are done.
+    // Keywords "inherit", "initial", "unset", and "revert" can not be
+    // mixed, so we are done.
     AppendValue(eCSSProperty_border_image_outset, value);
     return true;
   }
@@ -13800,8 +13825,8 @@ CSSParserImpl::ParseBorderImageRepeat(bool aAcceptsInherit)
   nsCSSValue value;
   if (aAcceptsInherit &&
       ParseSingleTokenVariant(value, VARIANT_INHERIT, nullptr)) {
-    // Keywords "inherit", "initial" and "unset" can not be mixed, so we
-    // are done.
+    // Keywords "inherit", "initial", "unset", and "revert" can not be
+    // mixed, so we are done.
     AppendValue(eCSSProperty_border_image_repeat, value);
     return true;
   }
@@ -13840,7 +13865,8 @@ CSSParserImpl::ParseBorderImage()
     AppendValue(eCSSProperty_border_image_width, value);
     AppendValue(eCSSProperty_border_image_outset, value);
     AppendValue(eCSSProperty_border_image_repeat, value);
-    // Keywords "inherit", "initial" and "unset" can't be mixed, so we are done.
+    // Keywords "inherit", "initial", "unset", and "revert" can not be
+    // mixed, so we are done.
     return true;
   }
 
@@ -13994,8 +14020,9 @@ CSSParserImpl::ParseBorderSide(const nsCSSPropertyID aPropIDs[],
     case eCSSUnit_Inherit:
     case eCSSUnit_Initial:
     case eCSSUnit_Unset:
+    case eCSSUnit_Revert:
       extraValue = values[0];
-      // Set value of border-image properties to initial/inherit/unset
+      // Set value of border-image properties to initial/inherit/unset/revert
       AppendValue(eCSSProperty_border_image_source, extraValue);
       AppendValue(eCSSProperty_border_image_slice, extraValue);
       AppendValue(eCSSProperty_border_image_width, extraValue);
@@ -14036,7 +14063,8 @@ bool
 CSSParserImpl::ParseBorderColors(nsCSSPropertyID aProperty)
 {
   nsCSSValue value;
-  // 'inherit', 'initial', 'unset' and 'none' are only allowed on their own
+  // 'inherit', 'initial', 'unset', 'revert', and 'none' are only allowed
+  // on their own
   if (!ParseSingleTokenVariant(value, VARIANT_INHERIT | VARIANT_NONE,
                                nullptr)) {
     nsCSSValueList *cur = value.SetListValue();
@@ -14423,8 +14451,8 @@ CSSParserImpl::ParseContent()
              "content keyword tables out of sync");
 
   nsCSSValue value;
-  // 'inherit', 'initial', 'unset', 'normal', 'none', and 'alt-content' must
-  // be alone
+  // 'inherit', 'initial', 'unset', 'revert', 'normal', 'none', and
+  // 'alt-content' must be alone
   if (!ParseSingleTokenVariant(value, VARIANT_HMK | VARIANT_NONE,
                                kContentSolitaryKWs)) {
     nsCSSValueList* cur = value.SetListValue();
@@ -14494,7 +14522,7 @@ bool
 CSSParserImpl::ParseCursor()
 {
   nsCSSValue value;
-  // 'inherit', 'initial' and 'unset' must be alone
+  // 'inherit', 'initial', 'unset', and 'revert' must be alone
   if (!ParseSingleTokenVariant(value, VARIANT_INHERIT, nullptr)) {
     nsCSSValueList* cur = value.SetListValue();
     for (;;) {
@@ -14538,7 +14566,8 @@ CSSParserImpl::ParseFont()
   if (ParseSingleTokenVariant(family, VARIANT_HK, nsCSSProps::kFontKTable)) {
     if (eCSSUnit_Inherit == family.GetUnit() ||
         eCSSUnit_Initial == family.GetUnit() ||
-        eCSSUnit_Unset == family.GetUnit()) {
+        eCSSUnit_Unset == family.GetUnit() ||
+        eCSSUnit_Revert == family.GetUnit()) {
       AppendValue(eCSSProperty__x_system_font, nsCSSValue(eCSSUnit_None));
       AppendValue(eCSSProperty_font_family, family);
       AppendValue(eCSSProperty_font_style, family);
@@ -14606,7 +14635,8 @@ CSSParserImpl::ParseFont()
   if (found < 0 ||
       eCSSUnit_Inherit == values[kFontStyleIndex].GetUnit() ||
       eCSSUnit_Initial == values[kFontStyleIndex].GetUnit() ||
-      eCSSUnit_Unset == values[kFontStyleIndex].GetUnit()) { // illegal data
+      eCSSUnit_Unset == values[kFontStyleIndex].GetUnit() ||
+      eCSSUnit_Revert == values[kFontStyleIndex].GetUnit() ) { // illegal data
     return false;
   }
   if ((found & (1 << kFontStyleIndex)) == 0) {
@@ -14664,7 +14694,8 @@ CSSParserImpl::ParseFont()
   if (ParseFamily(family)) {
     if (eCSSUnit_Inherit != family.GetUnit() &&
         eCSSUnit_Initial != family.GetUnit() &&
-        eCSSUnit_Unset != family.GetUnit()) {
+        eCSSUnit_Unset != family.GetUnit() &&
+        eCSSUnit_Revert != family.GetUnit()) {
       AppendValue(eCSSProperty__x_system_font, nsCSSValue(eCSSUnit_None));
       AppendValue(eCSSProperty_font_family, family);
       AppendValue(eCSSProperty_font_style, values[kFontStyleIndex]);
@@ -14709,7 +14740,8 @@ CSSParserImpl::ParseFontSynthesis(nsCSSValue& aValue)
   if (eCSSUnit_None == aValue.GetUnit() ||
       eCSSUnit_Initial == aValue.GetUnit() ||
       eCSSUnit_Inherit == aValue.GetUnit() ||
-      eCSSUnit_Unset == aValue.GetUnit())
+      eCSSUnit_Unset == aValue.GetUnit() ||
+      eCSSUnit_Revert == aValue.GetUnit() )
   {
     return true;
   }
@@ -15329,6 +15361,9 @@ CSSParserImpl::ParseFamily(nsCSSValue& aValue)
           return true;
         }
         break;
+      case eCSSKeyword_revert:
+        aValue.SetRevertValue(mLevel);
+        return true;
       case eCSSKeyword__moz_use_system_font:
         if (!IsParsingCompoundProperty()) {
           aValue.SetSystemFontValue();
@@ -15362,6 +15397,7 @@ CSSParserImpl::ParseFamily(nsCSSValue& aValue)
         case eCSSKeyword_inherit:
         case eCSSKeyword_initial:
         case eCSSKeyword_default:
+        case eCSSKeyword_revert:
         case eCSSKeyword__moz_use_system_font:
           return false;
         case eCSSKeyword_unset:
@@ -16034,7 +16070,7 @@ bool
 CSSParserImpl::ParseTextAlign(nsCSSValue& aValue, const KTableEntry aTable[])
 {
   if (ParseSingleTokenVariant(aValue, VARIANT_INHERIT, nullptr)) {
-    // 'inherit', 'initial' and 'unset' must be alone
+    // 'inherit', 'initial', 'unset', and 'revert' must be alone
     return true;
   }
 
@@ -16129,7 +16165,7 @@ bool
 CSSParserImpl::ParseTextOverflow(nsCSSValue& aValue)
 {
   if (ParseSingleTokenVariant(aValue, VARIANT_INHERIT, nullptr)) {
-    // 'inherit', 'initial' and 'unset' must be alone
+    // 'inherit', 'initial', 'unset', and 'revert' must be alone
     return true;
   }
 
@@ -16160,7 +16196,7 @@ CSSParserImpl::ParseTouchAction(nsCSSValue& aValue)
   }
 
   // Auto and None keywords aren't allowed in conjunction with others.
-  // Also inherit, initial and unset values are available.
+  // Also inherit, initial, unset, and revert values are available.
   if (eCSSUnit_Enumerated != aValue.GetUnit()) {
     return true;
   }
@@ -16665,7 +16701,7 @@ bool
 CSSParserImpl::ParseTransform(bool aIsPrefixed, bool aDisallowRelativeValues)
 {
   nsCSSValue value;
-  // 'inherit', 'initial', 'unset' and 'none' must be alone
+  // 'inherit', 'initial', 'unset', 'revert', and 'none' must be alone
   if (!ParseSingleTokenVariant(value, VARIANT_INHERIT | VARIANT_NONE,
                                nullptr)) {
     nsCSSValueSharedList* list = new nsCSSValueSharedList;
@@ -16951,7 +16987,8 @@ bool
 CSSParserImpl::ParseShapeOutside(nsCSSValue& aValue)
 {
   if (ParseSingleTokenVariant(aValue, VARIANT_HUO, nullptr)) {
-    // 'inherit', 'initial', 'unset', 'none', and <image> url must be alone.
+    // 'inherit', 'initial', 'unset', 'revert', 'none', and
+    // <image> url must be alone.
     return true;
   }
 
@@ -16975,9 +17012,10 @@ bool CSSParserImpl::ParseTransformOrigin(bool aPerspective)
   // a pair, and to keep the computation code simple.
   if (position.mXValue.GetUnit() == eCSSUnit_Inherit ||
       position.mXValue.GetUnit() == eCSSUnit_Initial ||
-      position.mXValue.GetUnit() == eCSSUnit_Unset) {
+      position.mXValue.GetUnit() == eCSSUnit_Unset ||
+      position.mXValue.GetUnit() == eCSSUnit_Revert) {
     MOZ_ASSERT(position.mXValue == position.mYValue,
-               "inherit/initial/unset only half?");
+               "inherit/initial/unset/revert only half?");
     AppendValue(prop, position.mXValue);
   } else {
     nsCSSValue value;
@@ -17154,7 +17192,7 @@ bool
 CSSParserImpl::ParseFilter()
 {
   nsCSSValue value;
-  // 'inherit', 'initial', 'unset' and 'none' must be alone
+  // 'inherit', 'initial', 'unset', 'revert', and 'none' must be alone
   if (!ParseSingleTokenVariant(value, VARIANT_INHERIT | VARIANT_NONE,
                                nullptr)) {
     nsCSSValueList* cur = value.SetListValue();
@@ -17183,7 +17221,7 @@ bool
 CSSParserImpl::ParseTransitionProperty()
 {
   nsCSSValue value;
-  // 'inherit', 'initial', 'unset' and 'none' must be alone
+  // 'inherit', 'initial', 'unset', 'revert', and 'none' must be alone
   if (!ParseSingleTokenVariant(value, VARIANT_INHERIT | VARIANT_NONE,
                                nullptr)) {
     // Accept a list of arbitrary identifiers.  They should be
@@ -17199,13 +17237,14 @@ CSSParserImpl::ParseTransitionProperty()
       }
       if (cur->mValue.GetUnit() == eCSSUnit_Ident) {
         nsDependentString str(cur->mValue.GetStringBufferValue());
-        // Exclude 'none', 'inherit', 'initial' and 'unset' according to the
-        // same rules as for 'counter-reset' in CSS 2.1.
+        // Exclude 'none', 'inherit', 'initial', 'unset', and 'revert'
+        // according to the same rules as for 'counter-reset' in CSS 2.1.
         if (str.LowerCaseEqualsLiteral("none") ||
             str.LowerCaseEqualsLiteral("inherit") ||
             str.LowerCaseEqualsLiteral("initial") ||
             (str.LowerCaseEqualsLiteral("unset") &&
-             nsLayoutUtils::UnsetValueEnabled())) {
+             nsLayoutUtils::UnsetValueEnabled()) ||
+            str.LowerCaseEqualsLiteral("revert")) {
           return false;
         }
       }
@@ -17346,9 +17385,9 @@ CSSParserImpl::ParseAnimationOrTransitionShorthand(
                  size_t aNumProperties)
 {
   nsCSSValue tempValue;
-  // first see if 'inherit', 'initial' or 'unset' is specified.  If one is,
-  // it can be the only thing specified, so don't attempt to parse any
-  // additional properties
+  // first see if 'inherit', 'initial', 'unset', or 'revert' is specified.
+  // If one is, it can be the only thing specified, so don't attempt to
+  // parse any additional properties
   if (ParseSingleTokenVariant(tempValue, VARIANT_INHERIT, nullptr)) {
     for (uint32_t i = 0; i < aNumProperties; ++i) {
       AppendValue(aProperties[i], tempValue);
@@ -17473,7 +17512,7 @@ CSSParserImpl::ParseTransition()
   // Make two checks on the list for 'transition-property':
   //   + If there is more than one item, then none of the items can be
   //     'none'.
-  //   + None of the items can be 'inherit', 'initial' or 'unset'.
+  //   + None of the items can be 'inherit', 'initial', 'unset', or 'revert'.
   {
     MOZ_ASSERT(kTransitionProperties[3] == eCSSProperty_transition_property,
                "array index mismatch");
@@ -17496,7 +17535,8 @@ CSSParserImpl::ParseTransition()
         if (str.EqualsLiteral("inherit") ||
             str.EqualsLiteral("initial") ||
             (str.EqualsLiteral("unset") &&
-             nsLayoutUtils::UnsetValueEnabled())) {
+             nsLayoutUtils::UnsetValueEnabled()) ||
+            str.EqualsLiteral("revert")) {
           return false;
         }
       }
@@ -17665,7 +17705,7 @@ CSSParserImpl::ParseShadowList(nsCSSPropertyID aProperty)
   bool isBoxShadow = aProperty == eCSSProperty_box_shadow;
 
   nsCSSValue value;
-  // 'inherit', 'initial', 'unset' and 'none' must be alone
+  // 'inherit', 'initial', 'unset', 'revert', and 'none' must be alone
   if (!ParseSingleTokenVariant(value, VARIANT_INHERIT | VARIANT_NONE,
                                nullptr)) {
     nsCSSValueList* cur = value.SetListValue();
@@ -17752,7 +17792,8 @@ CSSParserImpl::ParseDasharray()
 {
   nsCSSValue value;
 
-  // 'inherit', 'initial', 'unset' and 'none' are only allowed on their own
+  // 'inherit', 'initial', 'unset', 'revert' and 'none' are only allowed
+  // on their own
   if (!ParseSingleTokenVariant(value, VARIANT_INHERIT | VARIANT_NONE |
                                       VARIANT_OPENTYPE_SVG_KEYWORD,
                                nsCSSProps::kStrokeContextValueKTable)) {
@@ -18116,8 +18157,8 @@ CSSParserImpl::ParseValueWithVariables(CSSVariableDeclarations::Type* aType,
     }
   }
 
-  // Look for 'initial', 'inherit' or 'unset' as the first non-white space
-  // token.
+  // Look for 'initial', 'inherit', 'unset', or 'revert' as the first
+  // non-white space token.
   CSSVariableDeclarations::Type type = CSSVariableDeclarations::eTokenStream;
   if (mToken.mType == eCSSToken_Ident) {
     if (mToken.mIdent.LowerCaseEqualsLiteral("initial")) {
@@ -18126,6 +18167,8 @@ CSSParserImpl::ParseValueWithVariables(CSSVariableDeclarations::Type* aType,
       type = CSSVariableDeclarations::eInherit;
     } else if (mToken.mIdent.LowerCaseEqualsLiteral("unset")) {
       type = CSSVariableDeclarations::eUnset;
+    } else if (mToken.mIdent.LowerCaseEqualsLiteral("revert")) {
+      type = CSSVariableDeclarations::eRevert;
     }
   }
 
diff --git a/layout/style/nsCSSProps.h b/layout/style/nsCSSProps.h
index 567f7f7bfa..0995fba61b 100644
--- a/layout/style/nsCSSProps.h
+++ b/layout/style/nsCSSProps.h
@@ -44,7 +44,7 @@
 // 'inherit' and 'initial'
 #define VARIANT_OPACITY         0x008000  // Take floats and percents as input, output float.
 #define VARIANT_AUTO            0x010000  // A
-#define VARIANT_INHERIT         0x020000  // H eCSSUnit_Initial, eCSSUnit_Inherit, eCSSUnit_Unset
+#define VARIANT_INHERIT         0x020000  // H eCSSUnit_Initial, eCSSUnit_Inherit, eCSSUnit_Unset, eCSSUnit_Revert
 #define VARIANT_NONE            0x040000  // O
 #define VARIANT_NORMAL          0x080000  // M
 #define VARIANT_SYSFONT         0x100000  // eCSSUnit_System_Font

From 801d4a2db8d078852b1b04ce9cafc1370ff11084 Mon Sep 17 00:00:00 2001
From: Francis Dominic Fajardo <fofajardo@up.edu.ph>
Date: Fri, 20 Jun 2025 10:33:40 +0800
Subject: [PATCH 08/20] Issue #2045 - Part 5: Serialize shorthands using
 "revert" like those containing "unset"

---
 layout/style/CSSVariableDeclarations.cpp | 32 +++++++++++------
 layout/style/CSSVariableDeclarations.h   | 16 +++++++--
 layout/style/Declaration.cpp             | 44 ++++++++++++++++++------
 3 files changed, 68 insertions(+), 24 deletions(-)

diff --git a/layout/style/CSSVariableDeclarations.cpp b/layout/style/CSSVariableDeclarations.cpp
index 34a2bb0357..70194892c3 100644
--- a/layout/style/CSSVariableDeclarations.cpp
+++ b/layout/style/CSSVariableDeclarations.cpp
@@ -11,12 +11,13 @@
 #include "nsCSSScanner.h"
 #include "nsRuleData.h"
 
-// These three special string values are used to represent specified values of
-// 'initial', 'inherit' and 'unset'.  (Note that none of these are valid
-// variable values.)
+// These four special string values are used to represent specified values of
+// 'initial', 'inherit', 'unset', and 'revert'.  (Note that none of these are
+// valid variable values.)
 #define INITIAL_VALUE "!"
 #define INHERIT_VALUE ";"
 #define UNSET_VALUE   ")"
+#define REVERT_VALUE  ">"
 
 namespace mozilla {
 
@@ -83,6 +84,9 @@ CSSVariableDeclarations::Get(const nsAString& aName,
   } else if (value.EqualsLiteral(UNSET_VALUE)) {
     aType = eUnset;
     aTokenStream.Truncate();
+  } else if (value.EqualsLiteral(REVERT_VALUE)) {
+    aType = eRevert;
+    aTokenStream.Truncate();
   } else {
     aType = eTokenStream;
     aTokenStream = value;
@@ -96,7 +100,8 @@ CSSVariableDeclarations::PutTokenStream(const nsAString& aName,
 {
   MOZ_ASSERT(!aTokenStream.EqualsLiteral(INITIAL_VALUE) &&
              !aTokenStream.EqualsLiteral(INHERIT_VALUE) &&
-             !aTokenStream.EqualsLiteral(UNSET_VALUE));
+             !aTokenStream.EqualsLiteral(UNSET_VALUE) &&
+             !aTokenStream.EqualsLiteral(REVERT_VALUE));
   mVariables.Put(aName, aTokenStream);
 }
 
@@ -118,6 +123,12 @@ CSSVariableDeclarations::PutUnset(const nsAString& aName)
   mVariables.Put(aName, NS_LITERAL_STRING(UNSET_VALUE));
 }
 
+void
+CSSVariableDeclarations::PutRevert(const nsAString& aName)
+{
+  mVariables.Put(aName, NS_LITERAL_STRING(REVERT_VALUE));
+}
+
 void
 CSSVariableDeclarations::Remove(const nsAString& aName)
 {
@@ -160,12 +171,13 @@ CSSVariableDeclarations::AddVariablesToResolver(
                      eCSSTokenSerialization_Nothing,
                      false);
     } else if (value.EqualsLiteral(INHERIT_VALUE) ||
-               value.EqualsLiteral(UNSET_VALUE)) {
-      // Values of 'inherit' and 'unset' don't need any handling, since it means
-      // we just need to keep whatever value is currently in the resolver.  This
-      // is because the specified variable declarations already have only the
-      // winning declaration for the variable and no longer have any of the
-      // others.
+               value.EqualsLiteral(UNSET_VALUE) ||
+               value.EqualsLiteral(REVERT_VALUE)) {
+      // Values of 'inherit', 'unset', and 'revert' don't need any handling,
+      // since it means we just need to keep whatever value is currently in
+      // the resolver.  This is because the specified variable declarations
+      // already have only the winning declaration for the variable and no
+      // longer have any of the others.
     } else {
       // At this point, we don't know what token types are at the start and end
       // of the specified variable value.  These will be determined later during
diff --git a/layout/style/CSSVariableDeclarations.h b/layout/style/CSSVariableDeclarations.h
index 294e71a004..833daa7639 100644
--- a/layout/style/CSSVariableDeclarations.h
+++ b/layout/style/CSSVariableDeclarations.h
@@ -42,7 +42,8 @@ public:
     eTokenStream,  // a stream of CSS tokens (the usual type for variables)
     eInitial,      // 'initial'
     eInherit,      // 'inherit'
-    eUnset         // 'unset'
+    eUnset,        // 'unset'
+    eRevert        // 'revert'
   };
 
   /**
@@ -53,8 +54,8 @@ public:
    * @param aType Out parameter into which the type of the variable value will
    *   be stored.
    * @param aValue Out parameter into which the value of the variable will
-   *   be stored.  If the variable is 'initial', 'inherit' or 'unset', this will
-   *   be the empty string.
+   *   be stored.  If the variable is 'initial', 'inherit', 'unset', or
+   *   'revert', this will be the empty string.
    * @return Whether a variable with the given name was found.  When false
    *   is returned, aType and aValue will not be modified.
    */
@@ -87,6 +88,15 @@ public:
    */
   void PutUnset(const nsAString& aName);
 
+  /**
+   * Adds or modifies an existing entry in this set of variable declarations
+   * to have the value 'revert'.
+   *
+   * @param aName The variable name (not including any "--" prefix that would
+   *   be part of the custom property name) whose value is to be set.
+   */
+  void PutRevert(const nsAString& aName);
+
   /**
    * Adds or modifies an existing entry in this set of variable declarations
    * to have a token stream value.
diff --git a/layout/style/Declaration.cpp b/layout/style/Declaration.cpp
index 5d88feee26..f4197439f8 100644
--- a/layout/style/Declaration.cpp
+++ b/layout/style/Declaration.cpp
@@ -558,9 +558,9 @@ Declaration::GetPropertyValueInternal(
   //   (1) Since a shorthand sets all sub-properties, if some of its
   //       subproperties were not specified, we must return the empty
   //       string.
-  //   (2) Since 'inherit', 'initial' and 'unset' can only be specified
-  //       as the values for entire properties, we need to return the
-  //       empty string if some but not all of the subproperties have one
+  //   (2) Since 'inherit', 'initial', 'unset', and 'revert' can only be
+  //       specified as the values for entire properties, we need to return
+  //       the empty string if some but not all of the subproperties have one
   //       of those values.
   //   (3) Since a single value only makes sense with or without
   //       !important, we return the empty string if some values are
@@ -575,7 +575,7 @@ Declaration::GetPropertyValueInternal(
   // assigned to the shorthand.
   const nsCSSValue* tokenStream = nullptr;
   uint32_t totalCount = 0, importantCount = 0,
-           initialCount = 0, inheritCount = 0, unsetCount = 0,
+           initialCount = 0, inheritCount = 0, unsetCount = 0, revertCount = 0,
            matchingTokenStreamCount = 0, nonMatchingTokenStreamCount = 0;
   CSSPROPS_FOR_SHORTHAND_SUBPROPERTIES(p, aProperty,
                                        CSSEnabledState::eForAllContent) {
@@ -601,6 +601,8 @@ Declaration::GetPropertyValueInternal(
       ++initialCount;
     } else if (val->GetUnit() == eCSSUnit_Unset) {
       ++unsetCount;
+    } else if (val->GetUnit() == eCSSUnit_Revert) {
+      ++revertCount;
     } else if (val->GetUnit() == eCSSUnit_TokenStream) {
       if (val->GetTokenStreamValue()->mShorthandPropertyID == aProperty) {
         tokenStream = val;
@@ -632,9 +634,15 @@ Declaration::GetPropertyValueInternal(
                                               nsCSSValue::eNormalized);
     return;
   }
-  if (initialCount != 0 || inheritCount != 0 ||
-      unsetCount != 0 || nonMatchingTokenStreamCount != 0) {
-    // Case (2): partially initial, inherit, unset or token stream.
+  if (revertCount == totalCount) {
+    // Simplify serialization below by serializing revert up-front.
+    nsCSSValue(eCSSUnit_Revert).AppendToString(eCSSProperty_UNKNOWN, aValue,
+                                              nsCSSValue::eNormalized);
+    return;
+  }
+  if (initialCount != 0 || inheritCount != 0 || unsetCount != 0 ||
+      revertCount != 0 || nonMatchingTokenStreamCount != 0) {
+    // Case (2): partially initial, inherit, unset, revert, or token stream.
     return;
   }
   if (tokenStream) {
@@ -1455,6 +1463,7 @@ Declaration::GetPropertyValueInternal(
           case eCSSUnit_Inherit:
           case eCSSUnit_Initial:
           case eCSSUnit_Unset:
+          case eCSSUnit_Revert:
             return true;
           case eCSSUnit_Enumerated:
             // return false if there is a fallback value or <overflow-position>
@@ -1563,10 +1572,10 @@ Declaration::GetPropertyValueInternal(
       break;
     }
     case eCSSProperty_all:
-      // If we got here, then we didn't have all "inherit" or "initial" or
-      // "unset" values for all of the longhand property components of 'all'.
-      // There is no other possible value that is valid for all properties,
-      // so serialize as the empty string.
+      // If we got here, then we didn't have all "inherit", "initial", "unset",
+      // or "revert" values for all of the longhand property components of
+      // 'all'. There is no other possible value that is valid for all
+      // properties, so serialize as the empty string.
       break;
     default:
       MOZ_ASSERT(false, "no other shorthands");
@@ -1663,6 +1672,10 @@ Declaration::AppendVariableAndValueToString(const nsAString& aName,
       aResult.AppendLiteral("unset");
       break;
 
+    case CSSVariableDeclarations::eRevert:
+      aResult.AppendLiteral("revert");
+      break;
+
     default:
       MOZ_ASSERT(false, "unexpected variable value type");
   }
@@ -1899,6 +1912,10 @@ Declaration::GetVariableValue(const nsAString& aName, nsAString& aValue) const
         aValue.AppendLiteral("unset");
         break;
 
+      case CSSVariableDeclarations::eRevert:
+        aValue.AppendLiteral("revert");
+        break;
+
       default:
         MOZ_ASSERT(false, "unexpected variable value type");
     }
@@ -1964,6 +1981,11 @@ Declaration::AddVariable(const nsAString& aName,
       variables->PutUnset(aName);
       break;
 
+    case CSSVariableDeclarations::eRevert:
+      MOZ_ASSERT(aValue.IsEmpty());
+      variables->PutRevert(aName);
+      break;
+
     default:
       MOZ_ASSERT(false, "unexpected aType value");
   }

From c4b6135c9989d9edeb27853f9ab49a6574d2b643 Mon Sep 17 00:00:00 2001
From: Francis Dominic Fajardo <fofajardo@up.edu.ph>
Date: Fri, 20 Jun 2025 10:33:49 +0800
Subject: [PATCH 09/20] Issue #2045 - Part 6: Treat "revert" values as the same
 as "unset" when encountered in the rule node

---
 layout/style/nsRuleNode.cpp | 241 ++++++++++++++++++++++++++----------
 1 file changed, 176 insertions(+), 65 deletions(-)

diff --git a/layout/style/nsRuleNode.cpp b/layout/style/nsRuleNode.cpp
index 152fb01b2f..668debb5cb 100644
--- a/layout/style/nsRuleNode.cpp
+++ b/layout/style/nsRuleNode.cpp
@@ -945,7 +945,9 @@ static bool SetCoord(const nsCSSValue& aValue, nsStyleCoord& aCoord,
   } else if ((((aMask & SETCOORD_INHERIT) != 0) &&
             aValue.GetUnit() == eCSSUnit_Inherit) ||
            (((aMask & SETCOORD_UNSET_INHERIT) != 0) &&
-            aValue.GetUnit() == eCSSUnit_Unset)) {
+            aValue.GetUnit() == eCSSUnit_Unset) ||
+           (((aMask & SETCOORD_UNSET_INHERIT) != 0) &&
+            aValue.GetUnit() == eCSSUnit_Revert)) {
     aCoord = aParentCoord;  // just inherit value from parent
     aConditions.SetUncacheable();
   } else if (((aMask & SETCOORD_NORMAL) != 0) &&
@@ -963,6 +965,8 @@ static bool SetCoord(const nsCSSValue& aValue, nsStyleCoord& aCoord,
                                 aConditions);
   } else if (aValue.GetUnit() == eCSSUnit_Initial ||
            (aValue.GetUnit() == eCSSUnit_Unset &&
+            ((aMask & SETCOORD_UNSET_INITIAL) != 0)) ||
+           (aValue.GetUnit() == eCSSUnit_Revert &&
             ((aMask & SETCOORD_UNSET_INITIAL) != 0))) {
     if ((aMask & SETCOORD_INITIAL_AUTO) != 0) {
       aCoord.SetAutoValue();
@@ -1161,10 +1165,12 @@ SetComplexColor(const nsCSSValue& aValue,
     return;
   }
   if (unit == eCSSUnit_Initial ||
-      (UnsetTo == eUnsetInitial && unit == eCSSUnit_Unset)) {
+      (UnsetTo == eUnsetInitial && unit == eCSSUnit_Unset) ||
+      (UnsetTo == eUnsetInitial && unit == eCSSUnit_Revert)) {
     aResult = aInitialColor;
   } else if (unit == eCSSUnit_Inherit ||
-             (UnsetTo == eUnsetInherit && unit == eCSSUnit_Unset)) {
+             (UnsetTo == eUnsetInherit && unit == eCSSUnit_Unset) ||
+             (UnsetTo == eUnsetInherit && unit == eCSSUnit_Revert)) {
     aConditions.SetUncacheable();
     aResult = aParentColor;
   } else if (unit == eCSSUnit_EnumColor &&
@@ -1369,6 +1375,7 @@ static void SetStyleImage(nsStyleContext* aStyleContext,
       break;
     case eCSSUnit_Initial:
     case eCSSUnit_Unset:
+    case eCSSUnit_Revert:
     case eCSSUnit_None:
       break;
     case eCSSUnit_URL:
@@ -1560,6 +1567,7 @@ SetValue(const nsCSSValue& aValue, FieldT& aField,
     return;
 
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     if (aMask & SETVAL_UNSET_INHERIT) {
       aConditions.SetUncacheable();
       aField = aParentValue;
@@ -1610,7 +1618,7 @@ SetFactor(const nsCSSValue& aValue, float& aField, RuleNodeCacheConditions& aCon
       if (aField < 0.0f) {
         aField = 0.0f;
       }
-    } 
+    }
     if (aFlags & SETFCT_OPACITY) {
       if (aField < 0.0f) {
         aField = 0.0f;
@@ -1638,6 +1646,7 @@ SetFactor(const nsCSSValue& aValue, float& aField, RuleNodeCacheConditions& aCon
     break;
 
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     if (aFlags & SETFCT_UNSET_INHERIT) {
       aConditions.SetUncacheable();
       aField = aParentValue;
@@ -1940,12 +1949,14 @@ typedef nsRuleNode::RuleDetail
  * @param aSpecifiedCount to be incremented by one if the value is specified
  * @param aInheritedCount to be incremented by one if the value is set to inherit
  * @param aUnsetCount to be incremented by one if the value is set to unset
+ * @param aRevertCount to be incremented by one if the value is set to revert
  */
 inline void
 ExamineCSSValue(const nsCSSValue& aValue,
                 uint32_t& aSpecifiedCount,
                 uint32_t& aInheritedCount,
-                uint32_t& aUnsetCount)
+                uint32_t& aUnsetCount,
+                uint32_t& aRevertCount)
 {
   if (aValue.GetUnit() != eCSSUnit_Null) {
     ++aSpecifiedCount;
@@ -1953,6 +1964,8 @@ ExamineCSSValue(const nsCSSValue& aValue,
       ++aInheritedCount;
     } else if (aValue.GetUnit() == eCSSUnit_Unset) {
       ++aUnsetCount;
+    } else if (aValue.GetUnit() == eCSSUnit_Revert) {
+      ++aRevertCount;
     }
   }
 }
@@ -2242,7 +2255,8 @@ nsRuleNode::CheckSpecifiedProperties(const nsStyleStructID aSID,
            specified = 0,  // number that were specified for this node
            inherited = 0,  // number that were 'inherit' (and not
                            //   eCSSUnit_Inherit) for this node
-           unset = 0;      // number that were 'unset'
+           unset = 0,      // number that were 'unset'
+           revert = 0;     // number that were 'revert'
 
   // See comment in nsRuleData.h above mValueOffsets.
   MOZ_ASSERT(aRuleData->mValueOffsets[aSID] == 0,
@@ -2251,7 +2265,7 @@ nsRuleNode::CheckSpecifiedProperties(const nsStyleStructID aSID,
               *values_end = values + nsCSSProps::PropertyCountInStruct(aSID);
        values != values_end; ++values) {
     ++total;
-    ExamineCSSValue(*values, specified, inherited, unset);
+    ExamineCSSValue(*values, specified, inherited, unset, revert);
   }
 
   if (!nsCachedStyleData::IsReset(aSID)) {
@@ -3542,7 +3556,8 @@ nsRuleNode::SetFontSize(nsPresContext* aPresContext,
     // this becomes our cascading size
     *aSize = aSystemFont.size;
   } else if (eCSSUnit_Inherit == sizeValue->GetUnit() ||
-           eCSSUnit_Unset == sizeValue->GetUnit()) {
+             eCSSUnit_Unset == sizeValue->GetUnit() ||
+             eCSSUnit_Revert == sizeValue->GetUnit()) {
     aConditions.SetUncacheable();
     // We apply scriptlevel change for this case, because the default is
     // to inherit and we don't want explicit "inherit" to differ from the
@@ -3753,7 +3768,8 @@ nsRuleNode::SetFont(nsPresContext* aPresContext, nsStyleContext* aContext,
     aFont->mFont.systemFont = true;
     aFont->mGenericID = kGenericFont_NONE;
   } else if (eCSSUnit_Inherit == familyValue->GetUnit() ||
-           eCSSUnit_Unset == familyValue->GetUnit()) {
+             eCSSUnit_Unset == familyValue->GetUnit() ||
+             eCSSUnit_Revert == familyValue->GetUnit()) {
     aConditions.SetUncacheable();
     aFont->mFont.fontlist = aParentFont->mFont.fontlist;
     aFont->mFont.systemFont = aParentFont->mFont.systemFont;
@@ -3842,12 +3858,13 @@ nsRuleNode::SetFont(nsPresContext* aPresContext, nsStyleContext* aContext,
         break;
       }
     }
-  } else
+  } else {
     SetValue(*weightValue, aFont->mFont.weight, aConditions,
              SETVAL_INTEGER | SETVAL_UNSET_INHERIT,
              aParentFont->mFont.weight,
              defaultVariableFont->weight,
              Unused, Unused, Unused, systemFont.weight);
+  }
 
   // font-stretch: enum, inherit, initial, -moz-system-font
   SetValue(*aRuleData->ValueForFontStretch(),
@@ -3896,7 +3913,8 @@ nsRuleNode::SetFont(nsPresContext* aPresContext, nsStyleContext* aContext,
                                       (aParentFont->mMathDisplay ==
                                        NS_MATHML_DISPLAYSTYLE_INLINE ? 1 : 0));
   } else if (eCSSUnit_Inherit == scriptLevelValue->GetUnit() ||
-           eCSSUnit_Unset == scriptLevelValue->GetUnit()) {
+             eCSSUnit_Unset == scriptLevelValue->GetUnit() ||
+             eCSSUnit_Revert == scriptLevelValue->GetUnit()) {
     aConditions.SetUncacheable();
     aFont->mScriptLevel = aParentFont->mScriptLevel;
   } else if (eCSSUnit_Initial == scriptLevelValue->GetUnit()) {
@@ -3928,6 +3946,7 @@ nsRuleNode::SetFont(nsPresContext* aPresContext, nsStyleContext* aContext,
   switch (variantAlternatesValue->GetUnit()) {
   case eCSSUnit_Inherit:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     aFont->mFont.CopyAlternates(aParentFont->mFont);
     aConditions.SetUncacheable();
     break;
@@ -4023,6 +4042,7 @@ nsRuleNode::SetFont(nsPresContext* aPresContext, nsStyleContext* aContext,
 
   case eCSSUnit_Inherit:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     aConditions.SetUncacheable();
     aFont->mFont.fontFeatureSettings = aParentFont->mFont.fontFeatureSettings;
     break;
@@ -4046,7 +4066,8 @@ nsRuleNode::SetFont(nsPresContext* aPresContext, nsStyleContext* aContext,
   const nsCSSValue* languageOverrideValue =
     aRuleData->ValueForFontLanguageOverride();
   if (eCSSUnit_Inherit == languageOverrideValue->GetUnit() ||
-      eCSSUnit_Unset == languageOverrideValue->GetUnit()) {
+      eCSSUnit_Unset == languageOverrideValue->GetUnit() ||
+      eCSSUnit_Revert == languageOverrideValue->GetUnit()) {
     aConditions.SetUncacheable();
     aFont->mFont.languageOverride = aParentFont->mFont.languageOverride;
   } else if (eCSSUnit_Normal == languageOverrideValue->GetUnit() ||
@@ -4063,8 +4084,9 @@ nsRuleNode::SetFont(nsPresContext* aPresContext, nsStyleContext* aContext,
   switch (minFontSizeRatio->GetUnit()) {
     case eCSSUnit_Null:
       break;
-    case eCSSUnit_Unset:
     case eCSSUnit_Inherit:
+    case eCSSUnit_Unset:
+    case eCSSUnit_Revert:
       aFont->mMinFontSizeRatio = aParentFont->mMinFontSizeRatio;
       aConditions.SetUncacheable();
       break;
@@ -4909,7 +4931,8 @@ nsRuleNode::ComputeTextData(void* aStartStruct,
         NS_NOTYETIMPLEMENTED("align string");
       }
     } else if (eCSSUnit_Inherit == textAlignValue->GetUnit() ||
-               eCSSUnit_Unset == textAlignValue->GetUnit()) {
+               eCSSUnit_Unset == textAlignValue->GetUnit() ||
+               eCSSUnit_Revert == textAlignValue->GetUnit()) {
       text->mTextAlignTrue = parentText->mTextAlignTrue;
     }
     SetValue(*textAlignValue, text->mTextAlign, conditions,
@@ -4932,7 +4955,8 @@ nsRuleNode::ComputeTextData(void* aStartStruct,
       }
     }
   } else if (eCSSUnit_Inherit == textAlignLastValue->GetUnit() ||
-             eCSSUnit_Unset == textAlignLastValue->GetUnit()) {
+             eCSSUnit_Unset == textAlignLastValue->GetUnit() ||
+             eCSSUnit_Revert == textAlignLastValue->GetUnit()) {
     text->mTextAlignLastTrue = parentText->mTextAlignLastTrue;
   }
   SetValue(*textAlignLastValue, text->mTextAlignLast,
@@ -5052,7 +5076,8 @@ nsRuleNode::ComputeTextData(void* aStartStruct,
       break;
     }
     case eCSSUnit_Inherit:
-    case eCSSUnit_Unset: {
+    case eCSSUnit_Unset:
+    case eCSSUnit_Revert: {
       conditions.SetUncacheable();
       text->mTextEmphasisStyle = parentText->mTextEmphasisStyle;
       text->mTextEmphasisStyleString = parentText->mTextEmphasisStyleString;
@@ -5168,7 +5193,8 @@ nsRuleNode::ComputeTextResetData(void* aStartStruct,
     conditions.SetUncacheable();
     text->mTextDecorationLine = parentText->mTextDecorationLine;
   } else if (eCSSUnit_Initial == decorationLineValue->GetUnit() ||
-             eCSSUnit_Unset == decorationLineValue->GetUnit()) {
+             eCSSUnit_Unset == decorationLineValue->GetUnit() ||
+             eCSSUnit_Revert == decorationLineValue->GetUnit()) {
     text->mTextDecorationLine = NS_STYLE_TEXT_DECORATION_LINE_NONE;
   }
 
@@ -5188,7 +5214,8 @@ nsRuleNode::ComputeTextResetData(void* aStartStruct,
     text->mTextDecorationStyle = parentText->mTextDecorationStyle;
     conditions.SetUncacheable();
   } else if (eCSSUnit_Initial == decorationStyleValue->GetUnit() ||
-             eCSSUnit_Unset == decorationStyleValue->GetUnit()) {
+             eCSSUnit_Unset == decorationStyleValue->GetUnit() ||
+             eCSSUnit_Revert == decorationStyleValue->GetUnit()) {
     text->mTextDecorationStyle = NS_STYLE_TEXT_DECORATION_STYLE_SOLID;
   }
 
@@ -5196,7 +5223,8 @@ nsRuleNode::ComputeTextResetData(void* aStartStruct,
   const nsCSSValue* textOverflowValue =
     aRuleData->ValueForTextOverflow();
   if (eCSSUnit_Initial == textOverflowValue->GetUnit() ||
-      eCSSUnit_Unset == textOverflowValue->GetUnit()) {
+      eCSSUnit_Unset == textOverflowValue->GetUnit() ||
+      eCSSUnit_Revert == textOverflowValue->GetUnit()) {
     text->mTextOverflow = nsStyleTextOverflow();
   } else if (eCSSUnit_Inherit == textOverflowValue->GetUnit()) {
     conditions.SetUncacheable();
@@ -5265,6 +5293,7 @@ nsRuleNode::ComputeTextResetData(void* aStartStruct,
     text->mInitialLetterSize = parentText->mInitialLetterSize;
   } else if (initialLetterValue->GetUnit() == eCSSUnit_Initial ||
              initialLetterValue->GetUnit() == eCSSUnit_Unset ||
+             initialLetterValue->GetUnit() == eCSSUnit_Revert ||
              initialLetterValue->GetUnit() == eCSSUnit_Normal) {
     // Use invalid values in initial-letter property to mean normal. So we can
     // determine whether it is normal by checking mInitialLetterSink == 0.
@@ -5312,7 +5341,8 @@ nsRuleNode::ComputeUserInterfaceData(void* aStartStruct,
     ui->mCursorImages.Clear();
 
     if (cursorUnit == eCSSUnit_Inherit ||
-        cursorUnit == eCSSUnit_Unset) {
+        cursorUnit == eCSSUnit_Unset ||
+        cursorUnit == eCSSUnit_Revert) {
       conditions.SetUncacheable();
       ui->mCursor = parentUI->mCursor;
       ui->mCursorImages = parentUI->mCursorImages;
@@ -5694,7 +5724,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
                  "should have made conditions.Cacheable() false above");
       transition->SetDelay(parentDisplay->mTransitions[i].GetDelay());
     } else if (delay.unit == eCSSUnit_Initial ||
-               delay.unit == eCSSUnit_Unset) {
+               delay.unit == eCSSUnit_Unset ||
+               delay.unit == eCSSUnit_Revert) {
       transition->SetDelay(0.0);
     } else if (delay.list) {
       switch (delay.list->mValue.GetUnit()) {
@@ -5721,7 +5752,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
                  "should have made conditions.Cacheable() false above");
       transition->SetDuration(parentDisplay->mTransitions[i].GetDuration());
     } else if (duration.unit == eCSSUnit_Initial ||
-               duration.unit == eCSSUnit_Unset) {
+               duration.unit == eCSSUnit_Unset ||
+               duration.unit == eCSSUnit_Revert) {
       transition->SetDuration(0.0);
     } else if (duration.list) {
       switch (duration.list->mValue.GetUnit()) {
@@ -5747,7 +5779,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
                  "should have made conditions.Cacheable() false above");
       transition->CopyPropertyFrom(parentDisplay->mTransitions[i]);
     } else if (property.unit == eCSSUnit_Initial ||
-               property.unit == eCSSUnit_Unset) {
+               property.unit == eCSSUnit_Unset ||
+               property.unit == eCSSUnit_Revert) {
       transition->SetProperty(eCSSPropertyExtra_all_properties);
     } else if (property.unit == eCSSUnit_None) {
       transition->SetProperty(eCSSPropertyExtra_no_properties);
@@ -5786,7 +5819,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
       transition->SetTimingFunction(
         parentDisplay->mTransitions[i].GetTimingFunction());
     } else if (timingFunction.unit == eCSSUnit_Initial ||
-               timingFunction.unit == eCSSUnit_Unset) {
+               timingFunction.unit == eCSSUnit_Unset ||
+               timingFunction.unit == eCSSUnit_Revert) {
       transition->SetTimingFunction(
         nsTimingFunction(NS_STYLE_TRANSITION_TIMING_FUNCTION_EASE));
     } else if (timingFunction.list) {
@@ -5856,7 +5890,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
                  "should have made conditions.Cacheable() false above");
       animation->SetDelay(parentDisplay->mAnimations[i].GetDelay());
     } else if (animDelay.unit == eCSSUnit_Initial ||
-               animDelay.unit == eCSSUnit_Unset) {
+               animDelay.unit == eCSSUnit_Unset ||
+               animDelay.unit == eCSSUnit_Revert) {
       animation->SetDelay(0.0);
     } else if (animDelay.list) {
       switch (animDelay.list->mValue.GetUnit()) {
@@ -5883,7 +5918,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
                  "should have made conditions.Cacheable() false above");
       animation->SetDuration(parentDisplay->mAnimations[i].GetDuration());
     } else if (animDuration.unit == eCSSUnit_Initial ||
-               animDuration.unit == eCSSUnit_Unset) {
+               animDuration.unit == eCSSUnit_Unset ||
+               animDuration.unit == eCSSUnit_Revert) {
       animation->SetDuration(0.0);
     } else if (animDuration.list) {
       switch (animDuration.list->mValue.GetUnit()) {
@@ -5909,7 +5945,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
                  "should have made conditions.Cacheable() false above");
       animation->SetName(parentDisplay->mAnimations[i].GetName());
     } else if (animName.unit == eCSSUnit_Initial ||
-               animName.unit == eCSSUnit_Unset) {
+               animName.unit == eCSSUnit_Unset ||
+               animName.unit == eCSSUnit_Revert) {
       animation->SetName(EmptyString());
     } else if (animName.list) {
       switch (animName.list->mValue.GetUnit()) {
@@ -5941,7 +5978,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
       animation->SetTimingFunction(
         parentDisplay->mAnimations[i].GetTimingFunction());
     } else if (animTimingFunction.unit == eCSSUnit_Initial ||
-               animTimingFunction.unit == eCSSUnit_Unset) {
+               animTimingFunction.unit == eCSSUnit_Unset ||
+               animTimingFunction.unit == eCSSUnit_Revert) {
       animation->SetTimingFunction(
         nsTimingFunction(NS_STYLE_TRANSITION_TIMING_FUNCTION_EASE));
     } else if (animTimingFunction.list) {
@@ -5960,7 +5998,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
                  "should have made conditions.Cacheable() false above");
       animation->SetDirection(parentDisplay->mAnimations[i].GetDirection());
     } else if (animDirection.unit == eCSSUnit_Initial ||
-               animDirection.unit == eCSSUnit_Unset) {
+               animDirection.unit == eCSSUnit_Unset ||
+               animDirection.unit == eCSSUnit_Revert) {
       animation->SetDirection(dom::PlaybackDirection::Normal);
     } else if (animDirection.list) {
       MOZ_ASSERT(animDirection.list->mValue.GetUnit() == eCSSUnit_Enumerated,
@@ -5980,7 +6019,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
                  "should have made conditions.Cacheable() false above");
       animation->SetFillMode(parentDisplay->mAnimations[i].GetFillMode());
     } else if (animFillMode.unit == eCSSUnit_Initial ||
-               animFillMode.unit == eCSSUnit_Unset) {
+               animFillMode.unit == eCSSUnit_Unset ||
+               animFillMode.unit == eCSSUnit_Revert) {
       animation->SetFillMode(dom::FillMode::None);
     } else if (animFillMode.list) {
       MOZ_ASSERT(animFillMode.list->mValue.GetUnit() == eCSSUnit_Enumerated,
@@ -6001,7 +6041,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
                  "should have made conditions.Cacheable() false above");
       animation->SetPlayState(parentDisplay->mAnimations[i].GetPlayState());
     } else if (animPlayState.unit == eCSSUnit_Initial ||
-               animPlayState.unit == eCSSUnit_Unset) {
+               animPlayState.unit == eCSSUnit_Unset ||
+               animPlayState.unit == eCSSUnit_Revert) {
       animation->SetPlayState(NS_STYLE_ANIMATION_PLAY_STATE_RUNNING);
     } else if (animPlayState.list) {
       MOZ_ASSERT(animPlayState.list->mValue.GetUnit() == eCSSUnit_Enumerated,
@@ -6021,7 +6062,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
                  "should have made conditions.Cacheable() false above");
       animation->SetIterationCount(parentDisplay->mAnimations[i].GetIterationCount());
     } else if (animIterationCount.unit == eCSSUnit_Initial ||
-               animIterationCount.unit == eCSSUnit_Unset) {
+               animIterationCount.unit == eCSSUnit_Unset ||
+               animIterationCount.unit == eCSSUnit_Revert) {
       animation->SetIterationCount(1.0f);
     } else if (animIterationCount.list) {
       switch (animIterationCount.list->mValue.GetUnit()) {
@@ -6092,6 +6134,7 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
       break;
     case eCSSUnit_Initial:
     case eCSSUnit_Unset:
+    case eCSSUnit_Revert:
     case eCSSUnit_None:
       display->mScrollSnapPointsX.SetNoneValue();
       break;
@@ -6127,6 +6170,7 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
       break;
     case eCSSUnit_Initial:
     case eCSSUnit_Unset:
+    case eCSSUnit_Revert:
     case eCSSUnit_None:
       display->mScrollSnapPointsY.SetNoneValue();
       break;
@@ -6162,6 +6206,7 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
       break;
     case eCSSUnit_Initial:
     case eCSSUnit_Unset:
+    case eCSSUnit_Revert:
       display->mScrollSnapDestination.SetInitialZeroValues();
       break;
     case eCSSUnit_Inherit:
@@ -6181,8 +6226,9 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
       break;
     case eCSSUnit_Initial:
     case eCSSUnit_Unset:
+    case eCSSUnit_Revert:
     case eCSSUnit_None:
-      // Unset and Initial is none, indicated by an empty array
+      // Initial, Unset, and Revert are none, indicated by an empty array
       display->mScrollSnapCoordinate.Clear();
       break;
     case eCSSUnit_Inherit:
@@ -6196,7 +6242,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
         NS_ASSERTION(item->mValue.GetUnit() != eCSSUnit_Null &&
                      item->mValue.GetUnit() != eCSSUnit_Inherit &&
                      item->mValue.GetUnit() != eCSSUnit_Initial &&
-                     item->mValue.GetUnit() != eCSSUnit_Unset,
+                     item->mValue.GetUnit() != eCSSUnit_Unset &&
+                     item->mValue.GetUnit() != eCSSUnit_Revert,
                      "unexpected unit");
         Position* pos = display->mScrollSnapCoordinate.AppendElement();
         ComputePositionValue(aContext, item->mValue, *pos, conditions);
@@ -6244,8 +6291,9 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
       display->mBinding = nullptr;
     }
   } else if (eCSSUnit_None == bindingValue->GetUnit() ||
-           eCSSUnit_Initial == bindingValue->GetUnit() ||
-           eCSSUnit_Unset == bindingValue->GetUnit()) {
+             eCSSUnit_Initial == bindingValue->GetUnit() ||
+             eCSSUnit_Unset == bindingValue->GetUnit() ||
+             eCSSUnit_Revert == bindingValue->GetUnit()) {
     display->mBinding = nullptr;
   } else if (eCSSUnit_Inherit == bindingValue->GetUnit()) {
     conditions.SetUncacheable();
@@ -6285,7 +6333,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
       (NS_STYLE_PAGE_BREAK_AVOID != breakBeforeValue->GetIntValue() &&
        NS_STYLE_PAGE_BREAK_AUTO  != breakBeforeValue->GetIntValue());
   } else if (eCSSUnit_Initial == breakBeforeValue->GetUnit() ||
-           eCSSUnit_Unset == breakBeforeValue->GetUnit()) {
+             eCSSUnit_Unset == breakBeforeValue->GetUnit() ||
+             eCSSUnit_Revert == breakBeforeValue->GetUnit()) {
     display->mBreakBefore = false;
   } else if (eCSSUnit_Inherit == breakBeforeValue->GetUnit()) {
     conditions.SetUncacheable();
@@ -6298,7 +6347,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
       (NS_STYLE_PAGE_BREAK_AVOID != breakAfterValue->GetIntValue() &&
        NS_STYLE_PAGE_BREAK_AUTO  != breakAfterValue->GetIntValue());
   } else if (eCSSUnit_Initial == breakAfterValue->GetUnit() ||
-           eCSSUnit_Unset == breakAfterValue->GetUnit()) {
+             eCSSUnit_Unset == breakAfterValue->GetUnit() ||
+             eCSSUnit_Revert == breakAfterValue->GetUnit()) {
     display->mBreakAfter = false;
   } else if (eCSSUnit_Inherit == breakAfterValue->GetUnit()) {
     conditions.SetUncacheable();
@@ -6500,6 +6550,7 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
 
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
   case eCSSUnit_None:
     display->mSpecifiedTransform = nullptr;
     break;
@@ -6584,6 +6635,7 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
 
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
   case eCSSUnit_Auto:
     display->mWillChange.Clear();
     display->mWillChangeBitField = 0;
@@ -6600,7 +6652,8 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
                 SETCOORD_LPH | SETCOORD_ENUMERATED | SETCOORD_STORE_CALC,
                 aContext, mPresContext, conditions)) {
     if (eCSSUnit_Initial == verticalAlignValue->GetUnit() ||
-        eCSSUnit_Unset == verticalAlignValue->GetUnit()) {
+        eCSSUnit_Unset == verticalAlignValue->GetUnit() ||
+        eCSSUnit_Revert == verticalAlignValue->GetUnit()) {
       display->mVerticalAlign.SetIntValue(NS_STYLE_VERTICAL_ALIGN_BASELINE,
                                           eStyleUnit_Enumerated);
     }
@@ -6711,6 +6764,7 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
     case eCSSUnit_None:
     case eCSSUnit_Initial:
     case eCSSUnit_Unset:
+    case eCSSUnit_Revert:
       display->mShapeOutside = StyleShapeOutside();
       break;
     case eCSSUnit_Inherit:
@@ -6789,7 +6843,8 @@ nsRuleNode::ComputeVisibilityData(void* aStartStruct,
   // image-orientation: enum, inherit, initial
   const nsCSSValue* orientation = aRuleData->ValueForImageOrientation();
   if (orientation->GetUnit() == eCSSUnit_Inherit ||
-      orientation->GetUnit() == eCSSUnit_Unset) {
+      orientation->GetUnit() == eCSSUnit_Unset ||
+      orientation->GetUnit() == eCSSUnit_Revert) {
     conditions.SetUncacheable();
     visibility->mImageOrientation = parentVisibility->mImageOrientation;
   } else if (orientation->GetUnit() == eCSSUnit_Initial) {
@@ -6849,7 +6904,8 @@ nsRuleNode::ComputeColorData(void* aStartStruct,
   const nsCSSValue* colorValue = aRuleData->ValueForColor();
   if ((colorValue->GetUnit() == eCSSUnit_EnumColor &&
        colorValue->GetIntValue() == NS_COLOR_CURRENTCOLOR) ||
-      colorValue->GetUnit() == eCSSUnit_Unset) {
+       colorValue->GetUnit() == eCSSUnit_Unset ||
+       colorValue->GetUnit() == eCSSUnit_Revert) {
     color->mColor = parentColor->mColor;
     conditions.SetUncacheable();
   } else if (colorValue->GetUnit() == eCSSUnit_Initial) {
@@ -7158,7 +7214,8 @@ struct BackgroundItemComputer<nsCSSValuePairList, nsStyleImageLayers::Size>
           const nsCSSValue &widthValue = aSpecifiedValue->mXValue;
           MOZ_ASSERT(widthValue.GetUnit() != eCSSUnit_Inherit &&
                      widthValue.GetUnit() != eCSSUnit_Initial &&
-                     widthValue.GetUnit() != eCSSUnit_Unset,
+                     widthValue.GetUnit() != eCSSUnit_Unset &&
+                     widthValue.GetUnit() != eCSSUnit_Revert,
                      "initial/inherit/unset should already have been handled");
           MOZ_ASSERT(widthValue.GetUnit() == eCSSUnit_Enumerated &&
                      (widthValue.GetIntValue() == NS_STYLE_IMAGELAYER_SIZE_CONTAIN ||
@@ -7234,6 +7291,7 @@ SetImageLayerList(nsStyleContext* aStyleContext,
 
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     aRebuild = true;
     aItemCount = 1;
     aLayers[0].*aResultLocation = aInitialValue;
@@ -7248,7 +7306,8 @@ SetImageLayerList(nsStyleContext* aStyleContext,
       NS_ASSERTION(item->mValue.GetUnit() != eCSSUnit_Null &&
                    item->mValue.GetUnit() != eCSSUnit_Inherit &&
                    item->mValue.GetUnit() != eCSSUnit_Initial &&
-                   item->mValue.GetUnit() != eCSSUnit_Unset,
+                   item->mValue.GetUnit() != eCSSUnit_Unset &&
+                   item->mValue.GetUnit() != eCSSUnit_Revert,
                    "unexpected unit");
       ++aItemCount;
       aLayers.EnsureLengthAtLeast(aItemCount);
@@ -7305,6 +7364,7 @@ SetImageLayerPositionCoordList(
 
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     aRebuild = true;
     aItemCount = 1;
     aLayers[0].mPosition.*aResultLocation = aInitialValue;
@@ -7319,7 +7379,8 @@ SetImageLayerPositionCoordList(
       NS_ASSERTION(item->mValue.GetUnit() != eCSSUnit_Null &&
                    item->mValue.GetUnit() != eCSSUnit_Inherit &&
                    item->mValue.GetUnit() != eCSSUnit_Initial &&
-                   item->mValue.GetUnit() != eCSSUnit_Unset,
+                   item->mValue.GetUnit() != eCSSUnit_Unset &&
+                   item->mValue.GetUnit() != eCSSUnit_Revert,
                    "unexpected unit");
       ++aItemCount;
       aLayers.EnsureLengthAtLeast(aItemCount);
@@ -7372,6 +7433,7 @@ SetImageLayerPairList(nsStyleContext* aStyleContext,
 
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     aRebuild = true;
     aItemCount = 1;
     aLayers[0].*aResultLocation = aInitialValue;
@@ -7386,9 +7448,11 @@ SetImageLayerPairList(nsStyleContext* aStyleContext,
       NS_ASSERTION(item->mXValue.GetUnit() != eCSSUnit_Inherit &&
                    item->mXValue.GetUnit() != eCSSUnit_Initial &&
                    item->mXValue.GetUnit() != eCSSUnit_Unset &&
+                   item->mXValue.GetUnit() != eCSSUnit_Revert &&
                    item->mYValue.GetUnit() != eCSSUnit_Inherit &&
                    item->mYValue.GetUnit() != eCSSUnit_Initial &&
-                   item->mYValue.GetUnit() != eCSSUnit_Unset,
+                   item->mYValue.GetUnit() != eCSSUnit_Unset &&
+                   item->mYValue.GetUnit() != eCSSUnit_Revert,
                    "unexpected unit");
       ++aItemCount;
       aLayers.EnsureLengthAtLeast(aItemCount);
@@ -7496,7 +7560,8 @@ nsRuleNode::ComputeBackgroundData(void* aStartStruct,
   // background-color: color, string, inherit
   const nsCSSValue* backColorValue = aRuleData->ValueForBackgroundColor();
   if (eCSSUnit_Initial == backColorValue->GetUnit() ||
-      eCSSUnit_Unset == backColorValue->GetUnit()) {
+      eCSSUnit_Unset == backColorValue->GetUnit() ||
+      eCSSUnit_Revert == backColorValue->GetUnit()) {
     bg->mBackgroundColor = NS_RGBA(0, 0, 0, 0);
   } else if (!SetColor(*backColorValue, parentBG->mBackgroundColor,
                        mPresContext, aContext, bg->mBackgroundColor,
@@ -7650,6 +7715,7 @@ SetBorderImageRect(const nsCSSValue& aValue,
   case eCSSUnit_Inherit:
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     aRect.SetAllSidesTo(aValue);
     break;
   default:
@@ -7671,6 +7737,7 @@ SetBorderImagePair(const nsCSSValue& aValue,
   case eCSSUnit_Inherit:
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     aPair.SetBothValuesTo(aValue);
     break;
   default:
@@ -7705,6 +7772,7 @@ SetBorderImageSlice(const nsCSSValue& aValue,
   case eCSSUnit_Inherit:
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     aSlice = aValue;
     aFill = aValue;
     break;
@@ -7764,7 +7832,8 @@ nsRuleNode::ComputeBorderData(void* aStartStruct,
         border->SetBorderWidth(side,
                                parentBorder->GetComputedBorder().Side(side));
       } else if (eCSSUnit_Initial == value.GetUnit() ||
-               eCSSUnit_Unset == value.GetUnit()) {
+                 eCSSUnit_Unset == value.GetUnit() ||
+                 eCSSUnit_Revert == value.GetUnit()) {
         border->SetBorderWidth(side,
           (mPresContext->GetBorderWidthTable())[NS_STYLE_BORDER_WIDTH_MEDIUM]);
       } else {
@@ -7786,7 +7855,8 @@ nsRuleNode::ComputeBorderData(void* aStartStruct,
       if (eCSSUnit_Enumerated == unit) {
         border->SetBorderStyle(side, value.GetIntValue());
       } else if (eCSSUnit_Initial == unit ||
-               eCSSUnit_Unset == unit) {
+                 eCSSUnit_Unset == unit ||
+                 eCSSUnit_Revert == unit) {
         border->SetBorderStyle(side, NS_STYLE_BORDER_STYLE_NONE);
       } else if (eCSSUnit_Inherit == unit) {
         conditions.SetUncacheable();
@@ -7814,6 +7884,7 @@ nsRuleNode::ComputeBorderData(void* aStartStruct,
 
     case eCSSUnit_Initial:
     case eCSSUnit_Unset:
+    case eCSSUnit_Revert:
     case eCSSUnit_None:
       border->ClearBorderColors(side);
       break;
@@ -8029,7 +8100,8 @@ nsRuleNode::ComputeOutlineData(void* aStartStruct,
   // outline-width: length, enum, inherit
   const nsCSSValue* outlineWidthValue = aRuleData->ValueForOutlineWidth();
   if (eCSSUnit_Initial == outlineWidthValue->GetUnit() ||
-      eCSSUnit_Unset == outlineWidthValue->GetUnit()) {
+      eCSSUnit_Unset == outlineWidthValue->GetUnit() ||
+      eCSSUnit_Revert == outlineWidthValue->GetUnit()) {
     outline->mOutlineWidth =
       nsStyleCoord(NS_STYLE_BORDER_WIDTH_MEDIUM, eStyleUnit_Enumerated);
   } else {
@@ -8092,7 +8164,8 @@ nsRuleNode::ComputeOutlineData(void* aStartStruct,
   if (eCSSUnit_Enumerated == unit) {
     outline->mOutlineStyle = outlineStyleValue->GetIntValue();
   } else if (eCSSUnit_Initial == unit ||
-             eCSSUnit_Unset == unit) {
+             eCSSUnit_Unset == unit ||
+             eCSSUnit_Revert == unit) {
     outline->mOutlineStyle = NS_STYLE_BORDER_STYLE_NONE;
   } else if (eCSSUnit_Inherit == unit) {
     conditions.SetUncacheable();
@@ -8120,6 +8193,7 @@ nsRuleNode::ComputeListData(void* aStartStruct,
     break;
   case eCSSUnit_Inherit:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     conditions.SetUncacheable();
     list->SetQuotesInherit(parentList);
     break;
@@ -8157,8 +8231,9 @@ nsRuleNode::ComputeListData(void* aStartStruct,
   // list-style-type: string, none, inherit, initial
   const nsCSSValue* typeValue = aRuleData->ValueForListStyleType();
   switch (typeValue->GetUnit()) {
+    case eCSSUnit_Inherit:
     case eCSSUnit_Unset:
-    case eCSSUnit_Inherit: {
+    case eCSSUnit_Revert: {
       conditions.SetUncacheable();
       list->SetCounterStyle(parentList->GetCounterStyle());
       break;
@@ -8223,7 +8298,8 @@ nsRuleNode::ComputeListData(void* aStartStruct,
            eCSSUnit_Initial == imageValue->GetUnit()) {
     list->mListStyleImage = nullptr;
   } else if (eCSSUnit_Inherit == imageValue->GetUnit() ||
-           eCSSUnit_Unset == imageValue->GetUnit()) {
+             eCSSUnit_Unset == imageValue->GetUnit() ||
+             eCSSUnit_Revert == imageValue->GetUnit()) {
     conditions.SetUncacheable();
     list->mListStyleImage = parentList->mListStyleImage;
   }
@@ -8240,6 +8316,7 @@ nsRuleNode::ComputeListData(void* aStartStruct,
   switch (imageRegionValue->GetUnit()) {
   case eCSSUnit_Inherit:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     conditions.SetUncacheable();
     list->mImageRegion = parentList->mImageRegion;
     break;
@@ -8310,7 +8387,9 @@ SetGridTrackBreadth(const nsCSSValue& aValue,
     // For fit-content().
     aResult.SetNoneValue();
   } else {
-    MOZ_ASSERT(unit != eCSSUnit_Inherit && unit != eCSSUnit_Unset,
+    MOZ_ASSERT(unit != eCSSUnit_Inherit &&
+               unit != eCSSUnit_Unset &&
+               unit != eCSSUnit_Revert,
                "Unexpected value that would use dummyParentCoord");
     const nsStyleCoord dummyParentCoord;
     DebugOnly<bool> stored =
@@ -8378,6 +8457,7 @@ SetGridAutoColumnsRows(const nsCSSValue& aValue,
 
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     // The initial value is 'auto',
     // which computes to 'minmax(auto, auto)'.
     // (Explicitly-specified 'auto' values are handled in SetGridTrackSize.)
@@ -8434,6 +8514,7 @@ SetGridTrackList(const nsCSSValue& aValue,
 
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
   case eCSSUnit_None:
     aResult.mIsSubgrid = false;
     aResult.mLineNameLists.Clear();
@@ -8554,6 +8635,7 @@ SetGridTemplateAreas(const nsCSSValue& aValue,
 
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
   case eCSSUnit_None:
     *aResult = nullptr;
     break;
@@ -8581,6 +8663,7 @@ SetGridLine(const nsCSSValue& aValue,
 
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
   case eCSSUnit_Auto:
     aResult.SetAuto();
     break;
@@ -8837,6 +8920,7 @@ nsRuleNode::ComputePositionData(void* aStartStruct,
       break;
     case eCSSUnit_Initial:
     case eCSSUnit_Unset:
+    case eCSSUnit_Revert:
       pos->mObjectPosition.SetInitialPercentValues(0.5f);
       break;
     default:
@@ -8855,6 +8939,7 @@ nsRuleNode::ComputePositionData(void* aStartStruct,
       break;
     case eCSSUnit_Initial:
     case eCSSUnit_Unset:
+    case eCSSUnit_Revert:
       pos->mGridAutoFlow = NS_STYLE_GRID_AUTO_FLOW_ROW;
       break;
     default:
@@ -9065,6 +9150,7 @@ nsRuleNode::ComputeContentData(void* aStartStruct,
   case eCSSUnit_None:
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     // "normal", "none", "initial" and "unset" all mean no content
     content->AllocateContents(0);
     break;
@@ -9163,6 +9249,7 @@ nsRuleNode::ComputeContentData(void* aStartStruct,
   case eCSSUnit_None:
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     content->AllocateCounterIncrements(0);
     break;
 
@@ -9212,6 +9299,7 @@ nsRuleNode::ComputeContentData(void* aStartStruct,
   case eCSSUnit_None:
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     content->AllocateCounterResets(0);
     break;
 
@@ -9318,7 +9406,8 @@ nsRuleNode::ComputeXULData(void* aStartStruct,
     conditions.SetUncacheable();
     xul->mStretchStack = parentXUL->mStretchStack;
   } else if (eCSSUnit_Initial == stackSizingValue->GetUnit() ||
-             eCSSUnit_Unset == stackSizingValue->GetUnit()) {
+             eCSSUnit_Unset == stackSizingValue->GetUnit() ||
+             eCSSUnit_Revert == stackSizingValue->GetUnit()) {
     xul->mStretchStack = true;
   } else if (eCSSUnit_Enumerated == stackSizingValue->GetUnit()) {
     xul->mStretchStack = stackSizingValue->GetIntValue() ==
@@ -9350,7 +9439,8 @@ nsRuleNode::ComputeColumnData(void* aStartStruct,
   const nsCSSValue* columnCountValue = aRuleData->ValueForColumnCount();
   if (eCSSUnit_Auto == columnCountValue->GetUnit() ||
       eCSSUnit_Initial == columnCountValue->GetUnit() ||
-      eCSSUnit_Unset == columnCountValue->GetUnit()) {
+      eCSSUnit_Unset == columnCountValue->GetUnit() ||
+      eCSSUnit_Revert == columnCountValue->GetUnit()) {
     column->mColumnCount = NS_STYLE_COLUMN_COUNT_AUTO;
   } else if (eCSSUnit_Integer == columnCountValue->GetUnit()) {
     column->mColumnCount = columnCountValue->GetIntValue();
@@ -9365,7 +9455,8 @@ nsRuleNode::ComputeColumnData(void* aStartStruct,
   // column-rule-width: length, enum, inherit
   const nsCSSValue& widthValue = *aRuleData->ValueForColumnRuleWidth();
   if (eCSSUnit_Initial == widthValue.GetUnit() ||
-      eCSSUnit_Unset == widthValue.GetUnit()) {
+      eCSSUnit_Unset == widthValue.GetUnit() ||
+      eCSSUnit_Revert == widthValue.GetUnit()) {
     column->SetColumnRuleWidth(
         (mPresContext->GetBorderWidthTable())[NS_STYLE_BORDER_WIDTH_MEDIUM]);
   } else if (eCSSUnit_Enumerated == widthValue.GetUnit()) {
@@ -9399,7 +9490,8 @@ nsRuleNode::ComputeColumnData(void* aStartStruct,
   if (eCSSUnit_Enumerated == styleValue.GetUnit()) {
     column->mColumnRuleStyle = styleValue.GetIntValue();
   } else if (eCSSUnit_Initial == styleValue.GetUnit() ||
-           eCSSUnit_Unset == styleValue.GetUnit()) {
+             eCSSUnit_Unset == styleValue.GetUnit() ||
+             eCSSUnit_Revert == styleValue.GetUnit()) {
     column->mColumnRuleStyle = NS_STYLE_BORDER_STYLE_NONE;
   } else if (eCSSUnit_Inherit == styleValue.GetUnit()) {
     conditions.SetUncacheable();
@@ -9438,7 +9530,8 @@ SetSVGPaint(const nsCSSValue& aValue, const nsStyleSVGPaint& parentPaint,
   nscolor color;
 
   if (aValue.GetUnit() == eCSSUnit_Inherit ||
-      aValue.GetUnit() == eCSSUnit_Unset) {
+      aValue.GetUnit() == eCSSUnit_Unset ||
+      aValue.GetUnit() == eCSSUnit_Revert) {
     aResult = parentPaint;
     aConditions.SetUncacheable();
   } else if (aValue.GetUnit() == eCSSUnit_None) {
@@ -9510,7 +9603,8 @@ SetSVGOpacity(const nsCSSValue& aValue,
     // Fall back on fully opaque
     aOpacityField = 1.0f;
   } else if (eCSSUnit_Inherit == aValue.GetUnit() ||
-             eCSSUnit_Unset == aValue.GetUnit()) {
+             eCSSUnit_Unset == aValue.GetUnit() ||
+             eCSSUnit_Revert == aValue.GetUnit()) {
     aConditions.SetUncacheable();
     aOpacityField = aParentOpacity;
     aOpacityTypeField = aParentOpacityType;
@@ -9580,7 +9674,8 @@ nsRuleNode::ComputeSVGData(void* aStartStruct,
              eCSSUnit_Initial == markerEndValue->GetUnit()) {
     svg->mMarkerEnd = nullptr;
   } else if (eCSSUnit_Inherit == markerEndValue->GetUnit() ||
-             eCSSUnit_Unset == markerEndValue->GetUnit()) {
+             eCSSUnit_Unset == markerEndValue->GetUnit() ||
+             eCSSUnit_Revert == markerEndValue->GetUnit()) {
     conditions.SetUncacheable();
     svg->mMarkerEnd = parentSVG->mMarkerEnd;
   }
@@ -9593,7 +9688,8 @@ nsRuleNode::ComputeSVGData(void* aStartStruct,
              eCSSUnit_Initial == markerMidValue->GetUnit()) {
     svg->mMarkerMid = nullptr;
   } else if (eCSSUnit_Inherit == markerMidValue->GetUnit() ||
-             eCSSUnit_Unset == markerMidValue->GetUnit()) {
+             eCSSUnit_Unset == markerMidValue->GetUnit() ||
+             eCSSUnit_Revert == markerMidValue->GetUnit()) {
     conditions.SetUncacheable();
     svg->mMarkerMid = parentSVG->mMarkerMid;
   }
@@ -9605,6 +9701,8 @@ nsRuleNode::ComputeSVGData(void* aStartStruct,
   } else if (eCSSUnit_None == markerStartValue->GetUnit() ||
              eCSSUnit_Initial == markerStartValue->GetUnit()) {
     svg->mMarkerStart = nullptr;
+  } else if (eCSSUnit_Inherit == markerStartValue->GetUnit()) {
+
   } else if (eCSSUnit_Inherit == markerStartValue->GetUnit() ||
              eCSSUnit_Unset == markerStartValue->GetUnit()) {
     conditions.SetUncacheable();
@@ -9626,6 +9724,7 @@ nsRuleNode::ComputeSVGData(void* aStartStruct,
 
     case eCSSUnit_Inherit:
     case eCSSUnit_Unset:
+    case eCSSUnit_Revert:
       conditions.SetUncacheable();
       svg->mPaintOrder = parentSVG->mPaintOrder;
       break;
@@ -9658,6 +9757,7 @@ nsRuleNode::ComputeSVGData(void* aStartStruct,
 
   case eCSSUnit_Inherit:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
     conditions.SetUncacheable();
     svg->SetStrokeDasharrayFromObject(parentSVG->StrokeDasharrayFromObject());
     svg->mStrokeDasharray = parentSVG->mStrokeDasharray;
@@ -10057,7 +10157,8 @@ nsRuleNode::ComputeSVGResetData(void* aStartStruct,
   // stop-color:
   const nsCSSValue* stopColorValue = aRuleData->ValueForStopColor();
   if (eCSSUnit_Initial == stopColorValue->GetUnit() ||
-      eCSSUnit_Unset == stopColorValue->GetUnit()) {
+      eCSSUnit_Unset == stopColorValue->GetUnit() ||
+      eCSSUnit_Revert == stopColorValue->GetUnit()) {
     svgReset->mStopColor = NS_RGB(0, 0, 0);
   } else {
     SetColor(*stopColorValue, parentSVGReset->mStopColor,
@@ -10067,7 +10168,8 @@ nsRuleNode::ComputeSVGResetData(void* aStartStruct,
   // flood-color:
   const nsCSSValue* floodColorValue = aRuleData->ValueForFloodColor();
   if (eCSSUnit_Initial == floodColorValue->GetUnit() ||
-      eCSSUnit_Unset == floodColorValue->GetUnit()) {
+      eCSSUnit_Unset == floodColorValue->GetUnit() ||
+      eCSSUnit_Revert == floodColorValue->GetUnit()) {
     svgReset->mFloodColor = NS_RGB(0, 0, 0);
   } else {
     SetColor(*floodColorValue, parentSVGReset->mFloodColor,
@@ -10077,7 +10179,8 @@ nsRuleNode::ComputeSVGResetData(void* aStartStruct,
   // lighting-color:
   const nsCSSValue* lightingColorValue = aRuleData->ValueForLightingColor();
   if (eCSSUnit_Initial == lightingColorValue->GetUnit() ||
-      eCSSUnit_Unset == lightingColorValue->GetUnit()) {
+      eCSSUnit_Unset == lightingColorValue->GetUnit() ||
+      eCSSUnit_Revert == lightingColorValue->GetUnit()) {
     svgReset->mLightingColor = NS_RGB(255, 255, 255);
   } else {
     SetColor(*lightingColorValue, parentSVGReset->mLightingColor,
@@ -10093,6 +10196,7 @@ nsRuleNode::ComputeSVGResetData(void* aStartStruct,
     case eCSSUnit_None:
     case eCSSUnit_Initial:
     case eCSSUnit_Unset:
+    case eCSSUnit_Revert:
       svgReset->mClipPath = StyleClipPath();
       break;
     case eCSSUnit_Inherit:
@@ -10301,6 +10405,7 @@ nsRuleNode::ComputeEffectsData(void* aStartStruct,
     case eCSSUnit_None:
     case eCSSUnit_Initial:
     case eCSSUnit_Unset:
+    case eCSSUnit_Revert:
       effects->mFilters.Clear();
       break;
     case eCSSUnit_Inherit:
@@ -10337,6 +10442,7 @@ nsRuleNode::ComputeEffectsData(void* aStartStruct,
 
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
   case eCSSUnit_None:
     effects->mBoxShadow = nullptr;
     break;
@@ -10367,6 +10473,7 @@ nsRuleNode::ComputeEffectsData(void* aStartStruct,
 
   case eCSSUnit_Initial:
   case eCSSUnit_Unset:
+  case eCSSUnit_Revert:
   case eCSSUnit_Auto:
     effects->mClipFlags = NS_STYLE_CLIP_AUTO;
     effects->mClip.SetRect(0,0,0,0);
@@ -10678,10 +10785,12 @@ nsRuleNode::HasAuthorSpecifiedRules(nsStyleContext* aStyleContext,
           for (uint32_t i = 0; i < nValues; ++i) {
             nsCSSUnit unit = values[i]->GetUnit();
             if (unit != eCSSUnit_Null &&
+                unit != eCSSUnit_Revert &&
                 unit != eCSSUnit_Dummy &&
                 unit != eCSSUnit_DummyInherit) {
               if (unit == eCSSUnit_Inherit ||
-                  (i >= inheritedOffset && unit == eCSSUnit_Unset)) {
+                  (i >= inheritedOffset && unit == eCSSUnit_Unset) ||
+                  (i >= inheritedOffset && unit == eCSSUnit_Revert)) {
                 haveExplicitUAInherit = true;
                 values[i]->SetDummyInheritValue();
               } else {
@@ -10833,6 +10942,8 @@ nsRuleNode::ComputeColor(const nsCSSValue& aValue, nsPresContext* aPresContext,
              "aValue shouldn't have eCSSUnit_Initial");
   MOZ_ASSERT(aValue.GetUnit() != eCSSUnit_Unset,
              "aValue shouldn't have eCSSUnit_Unset");
+  MOZ_ASSERT(aValue.GetUnit() != eCSSUnit_Revert,
+             "aValue shouldn't have eCSSUnit_Revert");
 
   RuleNodeCacheConditions conditions;
   bool ok = SetColor(aValue, NS_RGB(0, 0, 0), aPresContext, aStyleContext,

From 166e98d2b97f875aba92b14dcd2d4b6f39ead77c Mon Sep 17 00:00:00 2001
From: Francis Dominic Fajardo <fofajardo@up.edu.ph>
Date: Mon, 30 Jun 2025 16:35:46 +0800
Subject: [PATCH 10/20] Issue #2045 - Part 7: Override revert values during
 presentation hint cascade

---
 layout/style/nsHTMLStyleSheet.cpp | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/layout/style/nsHTMLStyleSheet.cpp b/layout/style/nsHTMLStyleSheet.cpp
index 94b727bcc9..4d7de7293f 100644
--- a/layout/style/nsHTMLStyleSheet.cpp
+++ b/layout/style/nsHTMLStyleSheet.cpp
@@ -46,9 +46,11 @@ nsHTMLStyleSheet::HTMLColorRule::MapRuleInfoInto(nsRuleData* aRuleData)
 {
   if (aRuleData->mSIDs & NS_STYLE_INHERIT_BIT(Color)) {
     nsCSSValue* color = aRuleData->ValueForColor();
-    if (color->GetUnit() == eCSSUnit_Null &&
-        aRuleData->mPresContext->UseDocumentColors())
+    if ((color->GetUnit() == eCSSUnit_Null ||
+         color->GetUnit() == eCSSUnit_Revert) &&
+        aRuleData->mPresContext->UseDocumentColors()) {
       color->SetColorValue(mColor);
+    }
   }
 }
 
@@ -98,7 +100,8 @@ nsHTMLStyleSheet::TableTHRule::MapRuleInfoInto(nsRuleData* aRuleData)
 {
   if (aRuleData->mSIDs & NS_STYLE_INHERIT_BIT(Text)) {
     nsCSSValue* textAlign = aRuleData->ValueForTextAlign();
-    if (textAlign->GetUnit() == eCSSUnit_Null) {
+    if (textAlign->GetUnit() == eCSSUnit_Null ||
+        textAlign->GetUnit() == eCSSUnit_Revert) {
       textAlign->SetIntValue(NS_STYLE_TEXT_ALIGN_MOZ_CENTER_OR_INHERIT,
                              eCSSUnit_Enumerated);
     }
@@ -126,9 +129,11 @@ nsHTMLStyleSheet::TableQuirkColorRule::MapRuleInfoInto(nsRuleData* aRuleData)
     nsCSSValue* color = aRuleData->ValueForColor();
     // We do not check UseDocumentColors() here, because we want to
     // use the body color no matter what.
-    if (color->GetUnit() == eCSSUnit_Null)
+    if (color->GetUnit() == eCSSUnit_Null ||
+        color->GetUnit() == eCSSUnit_Revert) {
       color->SetIntValue(NS_STYLE_COLOR_INHERIT_FROM_BODY,
                          eCSSUnit_Enumerated);
+    }
   }
 }
 
@@ -153,7 +158,8 @@ nsHTMLStyleSheet::LangRule::MapRuleInfoInto(nsRuleData* aRuleData)
 {
   if (aRuleData->mSIDs & NS_STYLE_INHERIT_BIT(Font)) {
     nsCSSValue* lang = aRuleData->ValueForLang();
-    if (lang->GetUnit() == eCSSUnit_Null) {
+    if (lang->GetUnit() == eCSSUnit_Null ||
+        lang->GetUnit() == eCSSUnit_Revert) {
       lang->SetStringValue(mLang, eCSSUnit_Ident);
     }
   }

From a47f44e93d2b5ce26d26b6ddc506dd0f99a79a74 Mon Sep 17 00:00:00 2001
From: Francis Dominic Fajardo <fofajardo@up.edu.ph>
Date: Thu, 3 Jul 2025 17:51:18 +0800
Subject: [PATCH 11/20] Issue #2045 - Part 8: Remap revert keyword values to a
 higher cascade level

---
 layout/style/nsCSSDataBlock.cpp | 32 +++++++++++++++++++------------
 layout/style/nsRuleNode.cpp     | 34 ++++++++++++++++++++++-----------
 layout/style/nsRuleNode.h       |  3 ++-
 3 files changed, 45 insertions(+), 24 deletions(-)

diff --git a/layout/style/nsCSSDataBlock.cpp b/layout/style/nsCSSDataBlock.cpp
index e6045451d8..09ac37550e 100644
--- a/layout/style/nsCSSDataBlock.cpp
+++ b/layout/style/nsCSSDataBlock.cpp
@@ -174,7 +174,8 @@ MapSinglePropertyInto(nsCSSPropertyID aTargetProp,
   // then records any resulting ImageValue objects in the
   // CSSVariableImageTable, to give them the appropriate lifetime.
   MOZ_ASSERT(aTargetValue->GetUnit() == eCSSUnit_TokenStream ||
-             aTargetValue->GetUnit() == eCSSUnit_Null,
+             aTargetValue->GetUnit() == eCSSUnit_Null ||
+             aTargetValue->GetUnit() == eCSSUnit_Revert,
              "aTargetValue must only be a token stream (when re-parsing "
              "properties with variable references) or null");
 
@@ -316,19 +317,26 @@ nsCSSCompressedDataBlock::MapRuleInfoInto(nsRuleData *aRuleData) const
         EnsurePhysicalProperty(iProp, aRuleData);
       }
       nsCSSValue* target = aRuleData->ValueFor(iProp);
-      if (target->GetUnit() == eCSSUnit_Null) {
-        const nsCSSValue *val = ValueAtIndex(i);
-        // In order for variable resolution to have the right information
-        // about the stylesheet level of a value, that level needs to be
-        // stored on the token stream. We can't do that at creation time
-        // because the CSS parser (which creates the object) has no idea
-        // about the stylesheet level, so we do it here instead, where
-        // the rule walking will have just updated aRuleData.
-        if (val->GetUnit() == eCSSUnit_TokenStream) {
-          val->GetTokenStreamValue()->mLevel = aRuleData->mLevel;
+      if (target->GetUnit() == eCSSUnit_Revert) {
+        if (aRuleData->mLevel >= target->GetCascadeOriginValue()) {
+          continue;
         }
-        MapSinglePropertyInto(iProp, val, target, aRuleData);
+      } else if (target->GetUnit() != eCSSUnit_Null) {
+        continue;
       }
+      const nsCSSValue* val = ValueAtIndex(i);
+      // In order for variable resolution to have the right information
+      // about the stylesheet level of a value, that level needs to be
+      // stored on the token stream. We can't do that at creation time
+      // because the CSS parser (which creates the object) has no idea
+      // about the stylesheet level, so we do it here instead, where
+      // the rule walking will have just updated aRuleData.
+      if (val->GetUnit() == eCSSUnit_TokenStream) {
+        val->GetTokenStreamValue()->mLevel = aRuleData->mLevel;
+      } else if (val->GetUnit() == eCSSUnit_Revert) {
+        aRuleData->mConditions.SetUncacheable();
+      }
+      MapSinglePropertyInto(iProp, val, target, aRuleData);
     }
   }
 }
diff --git a/layout/style/nsRuleNode.cpp b/layout/style/nsRuleNode.cpp
index 668debb5cb..33c8ad5fa4 100644
--- a/layout/style/nsRuleNode.cpp
+++ b/layout/style/nsRuleNode.cpp
@@ -2248,7 +2248,8 @@ AreAllMathMLPropertiesUndefined(const nsRuleData* aRuleData)
 
 inline nsRuleNode::RuleDetail
 nsRuleNode::CheckSpecifiedProperties(const nsStyleStructID aSID,
-                                     const nsRuleData* aRuleData)
+                                     const nsRuleData* aRuleData,
+                                     bool& ignoreRuleCache)
 {
   // Build a count of the:
   uint32_t total = 0,      // total number of props in the struct
@@ -2323,6 +2324,8 @@ nsRuleNode::CheckSpecifiedProperties(const nsStyleStructID aSID,
     result = (*cb)(aRuleData, result);
   }
 
+  ignoreRuleCache = revert > 0;
+
   return result;
 }
 
@@ -2491,6 +2494,7 @@ nsRuleNode::WalkRuleTree(const nsStyleStructID aSID,
                                // will be the root.  (XXX misnamed)
   RuleDetail detail = eRuleNone;
   uint32_t bit = nsCachedStyleData::GetBitForSID(aSID);
+  bool ignoreRuleCache = false;
 
   while (ruleNode) {
     // See if this rule node has cached the fact that the remaining
@@ -2517,9 +2521,16 @@ nsRuleNode::WalkRuleTree(const nsStyleStructID aSID,
     // we'll miss it.
     startStruct = ruleNode->mStyleData.GetStyleData(aSID);
     if (startStruct) {
-      break; // We found a rule with fully specified data.  We don't
-    }        // need to go up the tree any further, since the remainder
-             // of this branch has already been computed.
+      // XXX: Ignore cached data if the previous rule node has revert values.
+      if (ignoreRuleCache) {
+        startStruct = nullptr;
+      } else {
+        // We found a rule with fully specified data.  We don't
+        // need to go up the tree any further, since the remainder
+        // of this branch has already been computed.
+        break;
+      }
+    }
 
     // Ask the rule to fill in the properties that it specifies.
     nsIStyleRule *rule = ruleNode->mRule;
@@ -2532,15 +2543,15 @@ nsRuleNode::WalkRuleTree(const nsStyleStructID aSID,
     // Now we check to see how many properties have been specified by
     // the rules we've examined so far.
     RuleDetail oldDetail = detail;
-    detail = CheckSpecifiedProperties(aSID, &ruleData);
+    detail = CheckSpecifiedProperties(aSID, &ruleData, ignoreRuleCache);
 
-    if (oldDetail == eRuleNone && detail != eRuleNone) {
+    if (oldDetail == eRuleNone && (detail != eRuleNone || ignoreRuleCache)) {
       highestNode = ruleNode;
     }
 
-    if (detail == eRuleFullReset ||
-        detail == eRuleFullMixed ||
-        detail == eRuleFullInherited) {
+    if (!ignoreRuleCache && (detail == eRuleFullReset ||
+                             detail == eRuleFullMixed ||
+                             detail == eRuleFullInherited)) {
       break; // We don't need to examine any more rules.  All properties
     }        // have been fully specified.
 
@@ -2576,7 +2587,7 @@ nsRuleNode::WalkRuleTree(const nsStyleStructID aSID,
   }
 
   if (recomputeDetail) {
-    detail = CheckSpecifiedProperties(aSID, &ruleData);
+    detail = CheckSpecifiedProperties(aSID, &ruleData, ignoreRuleCache);
   }
 
   NS_ASSERTION(!startStruct || (detail != eRuleFullReset &&
@@ -10804,7 +10815,8 @@ nsRuleNode::HasAuthorSpecifiedRules(nsStyleContext* aStyleContext,
           for (uint32_t i = 0; i < nValues; ++i) {
             if (values[i]->GetUnit() != eCSSUnit_Null &&
                 values[i]->GetUnit() != eCSSUnit_Dummy && // see above
-                values[i]->GetUnit() != eCSSUnit_DummyInherit) {
+                values[i]->GetUnit() != eCSSUnit_DummyInherit &&
+                values[i]->GetUnit() != eCSSUnit_Revert) {
               // If author colors are not allowed, only claim to have
               // author-specified rules if we're looking at a non-color
               // property or if we're looking at the background color and it's
diff --git a/layout/style/nsRuleNode.h b/layout/style/nsRuleNode.h
index 49fa8a027b..7ca3a165f9 100644
--- a/layout/style/nsRuleNode.h
+++ b/layout/style/nsRuleNode.h
@@ -787,7 +787,8 @@ protected:
                              nsStyleFont* aFont);
 
   inline RuleDetail CheckSpecifiedProperties(const nsStyleStructID aSID,
-                                             const nsRuleData* aRuleData);
+                                             const nsRuleData* aRuleData,
+                                             bool& ignoreRuleCache);
 
 private:
   nsRuleNode(nsPresContext* aPresContext, nsRuleNode* aParent,

From 5346e5565530a978683de58065fadc275404e1cc Mon Sep 17 00:00:00 2001
From: Francis Dominic Fajardo <fofajardo@up.edu.ph>
Date: Thu, 3 Jul 2025 19:34:30 +0800
Subject: [PATCH 12/20] Issue #2045 - Part 9: Include the revert keyword in the
 list of accepted values for CSS properties returned by inDOMUtils

---
 layout/inspector/inDOMUtils.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/layout/inspector/inDOMUtils.cpp b/layout/inspector/inDOMUtils.cpp
index fdae4543ed..793e973e3b 100644
--- a/layout/inspector/inDOMUtils.cpp
+++ b/layout/inspector/inDOMUtils.cpp
@@ -953,10 +953,11 @@ inDOMUtils::GetCSSValuesForProperty(const nsAString& aProperty,
       GetOtherValuesForProperty(propertyParserVariant, array);
     }
   }
-  // All CSS properties take initial, inherit and unset.
+  // All CSS properties take initial, inherit, unset, and revert.
   InsertNoDuplicates(array, NS_LITERAL_STRING("initial"));
   InsertNoDuplicates(array, NS_LITERAL_STRING("inherit"));
   InsertNoDuplicates(array, NS_LITERAL_STRING("unset"));
+  InsertNoDuplicates(array, NS_LITERAL_STRING("revert"));
 
   *aLength = array.Length();
   char16_t** ret =

From f0b8d1df2ce00fd8978260185447ff739039b736 Mon Sep 17 00:00:00 2001
From: Francis Dominic Fajardo <fofajardo@up.edu.ph>
Date: Thu, 3 Jul 2025 19:36:36 +0800
Subject: [PATCH 13/20] Issue #2045 - Part 10: Regenerate devtools CSS database
 and include the revert keyword in related devtools code

---
 .../inspector/shared/tooltips-overlay.js      |   2 +-
 devtools/client/shared/css-angle.js           |   3 +-
 .../client/shared/widgets/FilterWidget.js     |   2 +-
 devtools/shared/css/color.js                  |   3 +-
 .../shared/css/generated/properties-db.js     | 471 ++++++++++++++++++
 5 files changed, 477 insertions(+), 4 deletions(-)

diff --git a/devtools/client/inspector/shared/tooltips-overlay.js b/devtools/client/inspector/shared/tooltips-overlay.js
index 55f7e25ab5..1860587ddd 100644
--- a/devtools/client/inspector/shared/tooltips-overlay.js
+++ b/devtools/client/inspector/shared/tooltips-overlay.js
@@ -151,7 +151,7 @@ TooltipsOverlay.prototype = {
     // Font preview tooltip
     if (type === VIEW_NODE_VALUE_TYPE && prop.property === "font-family") {
       let value = prop.value.toLowerCase();
-      if (value !== "inherit" && value !== "unset" && value !== "initial") {
+      if (value !== "inherit" && value !== "unset" && value !== "initial" && value !== "revert") {
         tooltipType = TOOLTIP_FONTFAMILY_TYPE;
       }
     }
diff --git a/devtools/client/shared/css-angle.js b/devtools/client/shared/css-angle.js
index f3612ed843..aa01095e1d 100644
--- a/devtools/client/shared/css-angle.js
+++ b/devtools/client/shared/css-angle.js
@@ -9,7 +9,8 @@ const {CSS_ANGLEUNIT} = require("devtools/shared/css/properties-db");
 const SPECIALVALUES = new Set([
   "initial",
   "inherit",
-  "unset"
+  "unset",
+  "revert"
 ]);
 
 const {getCSSLexer} = require("devtools/shared/css/lexer");
diff --git a/devtools/client/shared/widgets/FilterWidget.js b/devtools/client/shared/widgets/FilterWidget.js
index 9cdb27a5ab..b3392b3fa7 100644
--- a/devtools/client/shared/widgets/FilterWidget.js
+++ b/devtools/client/shared/widgets/FilterWidget.js
@@ -99,7 +99,7 @@ const filterList = [
 ];
 
 // Valid values that shouldn't be parsed for filters.
-const SPECIAL_VALUES = new Set(["none", "unset", "initial", "inherit"]);
+const SPECIAL_VALUES = new Set(["none", "unset", "initial", "inherit", "revert"]);
 
 /**
  * A CSS Filter editor widget used to add/remove/modify
diff --git a/devtools/shared/css/color.js b/devtools/shared/css/color.js
index 98ddeff195..6dfd3db31e 100644
--- a/devtools/shared/css/color.js
+++ b/devtools/shared/css/color.js
@@ -19,7 +19,8 @@ const SPECIALVALUES = new Set([
   "initial",
   "inherit",
   "transparent",
-  "unset"
+  "unset",
+  "revert"
 ]);
 
 /**
diff --git a/devtools/shared/css/generated/properties-db.js b/devtools/shared/css/generated/properties-db.js
index 587f5704d1..f55e3111a2 100644
--- a/devtools/shared/css/generated/properties-db.js
+++ b/devtools/shared/css/generated/properties-db.js
@@ -51,6 +51,7 @@ exports.CSS_PROPERTIES = {
       "normal",
       "paused",
       "reverse",
+      "revert",
       "running",
       "step-end",
       "step-start",
@@ -69,6 +70,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -85,6 +87,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "normal",
       "reverse",
+      "revert",
       "unset"
     ]
   },
@@ -99,6 +102,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -115,6 +119,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -130,6 +135,7 @@ exports.CSS_PROPERTIES = {
       "infinite",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -143,6 +149,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -156,6 +163,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "paused",
+      "revert",
       "running",
       "unset"
     ]
@@ -177,6 +185,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "linear",
+      "revert",
       "step-end",
       "step-start",
       "steps",
@@ -265,6 +274,7 @@ exports.CSS_PROPERTIES = {
       "range-thumb",
       "resizer",
       "resizerpanel",
+      "revert",
       "scale-horizontal",
       "scale-vertical",
       "scalethumb-horizontal",
@@ -328,6 +338,7 @@ exports.CSS_PROPERTIES = {
       "hidden",
       "inherit",
       "initial",
+      "revert",
       "unset",
       "visible"
     ]
@@ -344,6 +355,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset",
       "url"
     ]
@@ -359,6 +371,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -391,6 +404,7 @@ exports.CSS_PROPERTIES = {
       "medium",
       "none",
       "outset",
+      "revert",
       "rgb",
       "rgba",
       "ridge",
@@ -416,6 +430,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -439,6 +454,7 @@ exports.CSS_PROPERTIES = {
       "inset",
       "none",
       "outset",
+      "revert",
       "ridge",
       "solid",
       "unset"
@@ -458,6 +474,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "thick",
       "thin",
       "unset"
@@ -494,6 +511,7 @@ exports.CSS_PROPERTIES = {
       "radial-gradient",
       "repeating-linear-gradient",
       "repeating-radial-gradient",
+      "revert",
       "unset",
       "url"
     ]
@@ -509,6 +527,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -523,6 +542,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -555,6 +575,7 @@ exports.CSS_PROPERTIES = {
       "medium",
       "none",
       "outset",
+      "revert",
       "rgb",
       "rgba",
       "ridge",
@@ -580,6 +601,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -603,6 +625,7 @@ exports.CSS_PROPERTIES = {
       "inset",
       "none",
       "outset",
+      "revert",
       "ridge",
       "solid",
       "unset"
@@ -622,6 +645,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "thick",
       "thin",
       "unset"
@@ -638,6 +662,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -653,6 +678,7 @@ exports.CSS_PROPERTIES = {
       "end",
       "inherit",
       "initial",
+      "revert",
       "start",
       "stretch",
       "unset"
@@ -669,6 +695,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "normal",
       "reverse",
+      "revert",
       "unset"
     ]
   },
@@ -683,6 +710,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -697,6 +725,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -712,6 +741,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "inline-axis",
+      "revert",
       "unset",
       "vertical"
     ]
@@ -728,6 +758,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "justify",
+      "revert",
       "start",
       "unset"
     ]
@@ -743,6 +774,7 @@ exports.CSS_PROPERTIES = {
       "content-box",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -758,6 +790,7 @@ exports.CSS_PROPERTIES = {
       "auto",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -772,6 +805,7 @@ exports.CSS_PROPERTIES = {
       "balance",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -790,6 +824,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -822,6 +857,7 @@ exports.CSS_PROPERTIES = {
       "medium",
       "none",
       "outset",
+      "revert",
       "rgb",
       "rgba",
       "ridge",
@@ -847,6 +883,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -870,6 +907,7 @@ exports.CSS_PROPERTIES = {
       "inset",
       "none",
       "outset",
+      "revert",
       "ridge",
       "solid",
       "unset"
@@ -889,6 +927,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "thick",
       "thin",
       "unset"
@@ -908,6 +947,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -927,6 +967,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -940,6 +981,7 @@ exports.CSS_PROPERTIES = {
       "hidden",
       "inherit",
       "initial",
+      "revert",
       "unset",
       "visible"
     ]
@@ -955,6 +997,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "margin-box",
+      "revert",
       "unset"
     ]
   },
@@ -967,6 +1010,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -980,6 +1024,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -994,6 +1039,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1009,6 +1055,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "manual",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -1021,6 +1068,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1039,6 +1087,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1057,6 +1106,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1072,6 +1122,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "inline",
+      "revert",
       "unset",
       "vertical"
     ]
@@ -1091,6 +1142,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1106,6 +1158,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1121,6 +1174,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1136,6 +1190,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1151,6 +1206,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1168,6 +1224,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1185,6 +1242,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1200,6 +1258,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -1215,6 +1274,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1228,6 +1288,7 @@ exports.CSS_PROPERTIES = {
       "ignore",
       "inherit",
       "initial",
+      "revert",
       "stretch-to-fit",
       "unset"
     ]
@@ -1246,6 +1307,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1263,6 +1325,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "justify",
       "left",
+      "revert",
       "right",
       "start",
       "unset"
@@ -1279,6 +1342,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -1291,6 +1355,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1306,6 +1371,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1320,6 +1386,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "preserve-3d",
+      "revert",
       "unset"
     ]
   },
@@ -1346,6 +1413,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "linear",
       "none",
+      "revert",
       "step-end",
       "step-start",
       "steps",
@@ -1363,6 +1431,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1377,6 +1446,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1391,6 +1461,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -1411,6 +1482,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "linear",
+      "revert",
       "step-end",
       "step-start",
       "steps",
@@ -1429,6 +1501,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "none",
       "normal",
+      "revert",
       "select-after",
       "select-all",
       "select-before",
@@ -1450,6 +1523,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -1464,6 +1538,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "read-only",
       "read-write",
+      "revert",
       "unset",
       "write-only"
     ]
@@ -1485,6 +1560,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "text",
       "toggle",
       "tri-state",
@@ -1503,6 +1579,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "no-drag",
+      "revert",
       "unset"
     ]
   },
@@ -1523,6 +1600,7 @@ exports.CSS_PROPERTIES = {
       "last baseline",
       "left",
       "normal",
+      "revert",
       "right",
       "space-around",
       "space-between",
@@ -1549,6 +1627,7 @@ exports.CSS_PROPERTIES = {
       "last baseline",
       "left",
       "normal",
+      "revert",
       "right",
       "self-end",
       "self-start",
@@ -1575,6 +1654,7 @@ exports.CSS_PROPERTIES = {
       "last baseline",
       "left",
       "normal",
+      "revert",
       "right",
       "self-end",
       "self-start",
@@ -1619,6 +1699,7 @@ exports.CSS_PROPERTIES = {
       "normal",
       "paused",
       "reverse",
+      "revert",
       "running",
       "step-end",
       "step-start",
@@ -1637,6 +1718,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1653,6 +1735,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "normal",
       "reverse",
+      "revert",
       "unset"
     ]
   },
@@ -1667,6 +1750,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1683,6 +1767,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -1698,6 +1783,7 @@ exports.CSS_PROPERTIES = {
       "infinite",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1711,6 +1797,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -1724,6 +1811,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "paused",
+      "revert",
       "running",
       "unset"
     ]
@@ -1745,6 +1833,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "linear",
+      "revert",
       "step-end",
       "step-start",
       "steps",
@@ -1833,6 +1922,7 @@ exports.CSS_PROPERTIES = {
       "range-thumb",
       "resizer",
       "resizerpanel",
+      "revert",
       "scale-horizontal",
       "scale-vertical",
       "scalethumb-horizontal",
@@ -1896,6 +1986,7 @@ exports.CSS_PROPERTIES = {
       "hidden",
       "inherit",
       "initial",
+      "revert",
       "unset",
       "visible"
     ]
@@ -1912,6 +2003,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "padding-box",
+      "revert",
       "text",
       "unset"
     ]
@@ -1928,6 +2020,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "padding-box",
+      "revert",
       "unset"
     ]
   },
@@ -1943,6 +2036,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1958,6 +2052,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -1973,6 +2068,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2007,6 +2103,7 @@ exports.CSS_PROPERTIES = {
       "radial-gradient",
       "repeating-linear-gradient",
       "repeating-radial-gradient",
+      "revert",
       "unset",
       "url"
     ]
@@ -2026,6 +2123,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2041,6 +2139,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2056,6 +2155,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2071,6 +2171,7 @@ exports.CSS_PROPERTIES = {
       "end",
       "inherit",
       "initial",
+      "revert",
       "start",
       "stretch",
       "unset"
@@ -2087,6 +2188,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "normal",
       "reverse",
+      "revert",
       "unset"
     ]
   },
@@ -2101,6 +2203,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2115,6 +2218,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2130,6 +2234,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "inline-axis",
+      "revert",
       "unset",
       "vertical"
     ]
@@ -2146,6 +2251,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "justify",
+      "revert",
       "start",
       "unset"
     ]
@@ -2162,6 +2268,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2176,6 +2283,7 @@ exports.CSS_PROPERTIES = {
       "content-box",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2190,6 +2298,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2216,6 +2325,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "max-content",
       "min-content",
+      "revert",
       "unset"
     ]
   },
@@ -2239,6 +2349,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "max-content",
       "min-content",
+      "revert",
       "unset"
     ]
   },
@@ -2253,6 +2364,7 @@ exports.CSS_PROPERTIES = {
       "column-reverse",
       "inherit",
       "initial",
+      "revert",
       "row",
       "row-reverse",
       "unset"
@@ -2271,6 +2383,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "nowrap",
+      "revert",
       "row",
       "row-reverse",
       "unset",
@@ -2289,6 +2402,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2303,6 +2417,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2316,6 +2431,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "nowrap",
+      "revert",
       "unset",
       "wrap",
       "wrap-reverse"
@@ -2338,6 +2454,7 @@ exports.CSS_PROPERTIES = {
       "last baseline",
       "left",
       "normal",
+      "revert",
       "right",
       "space-around",
       "space-between",
@@ -2396,6 +2513,7 @@ exports.CSS_PROPERTIES = {
       "repeat-y",
       "repeating-linear-gradient",
       "repeating-radial-gradient",
+      "revert",
       "round",
       "space",
       "stroke-box",
@@ -2419,6 +2537,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "no-clip",
       "padding-box",
+      "revert",
       "stroke-box",
       "unset",
       "view-box"
@@ -2436,6 +2555,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "intersect",
+      "revert",
       "subtract",
       "unset"
     ]
@@ -2464,6 +2584,7 @@ exports.CSS_PROPERTIES = {
       "radial-gradient",
       "repeating-linear-gradient",
       "repeating-radial-gradient",
+      "revert",
       "unset",
       "url"
     ]
@@ -2481,6 +2602,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "padding-box",
+      "revert",
       "stroke-box",
       "unset",
       "view-box"
@@ -2499,6 +2621,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2514,6 +2637,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2529,6 +2653,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2545,6 +2670,7 @@ exports.CSS_PROPERTIES = {
       "repeat",
       "repeat-x",
       "repeat-y",
+      "revert",
       "round",
       "space",
       "unset"
@@ -2562,6 +2688,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2576,6 +2703,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2591,6 +2719,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -2606,6 +2735,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2624,6 +2754,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -2641,6 +2772,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -2664,6 +2796,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "rgb",
       "rgba",
       "thick",
@@ -2687,6 +2820,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -2707,6 +2841,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "thick",
       "thin",
       "unset"
@@ -2721,6 +2856,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2736,6 +2872,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2750,6 +2887,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "preserve-3d",
+      "revert",
       "unset"
     ]
   },
@@ -2776,6 +2914,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "linear",
       "none",
+      "revert",
       "step-end",
       "step-start",
       "steps",
@@ -2793,6 +2932,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2807,6 +2947,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -2821,6 +2962,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -2841,6 +2983,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "linear",
+      "revert",
       "step-end",
       "step-start",
       "steps",
@@ -2864,6 +3007,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "text",
       "toggle",
       "tri-state",
@@ -2887,6 +3031,7 @@ exports.CSS_PROPERTIES = {
       "last baseline",
       "left",
       "normal",
+      "revert",
       "right",
       "space-around",
       "space-between",
@@ -2913,6 +3058,7 @@ exports.CSS_PROPERTIES = {
       "last baseline",
       "left",
       "normal",
+      "revert",
       "right",
       "self-end",
       "self-start",
@@ -2939,6 +3085,7 @@ exports.CSS_PROPERTIES = {
       "last baseline",
       "left",
       "normal",
+      "revert",
       "right",
       "self-end",
       "self-start",
@@ -3567,6 +3714,7 @@ exports.CSS_PROPERTIES = {
       "resizer",
       "resizerpanel",
       "reverse",
+      "revert",
       "rgb",
       "rgba",
       "ridge",
@@ -3764,6 +3912,7 @@ exports.CSS_PROPERTIES = {
       "normal",
       "paused",
       "reverse",
+      "revert",
       "running",
       "step-end",
       "step-start",
@@ -3782,6 +3931,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -3798,6 +3948,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "normal",
       "reverse",
+      "revert",
       "unset"
     ]
   },
@@ -3812,6 +3963,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -3828,6 +3980,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -3843,6 +3996,7 @@ exports.CSS_PROPERTIES = {
       "infinite",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -3856,6 +4010,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -3869,6 +4024,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "paused",
+      "revert",
       "running",
       "unset"
     ]
@@ -3890,6 +4046,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "linear",
+      "revert",
       "step-end",
       "step-start",
       "steps",
@@ -3906,6 +4063,7 @@ exports.CSS_PROPERTIES = {
       "hidden",
       "inherit",
       "initial",
+      "revert",
       "unset",
       "visible"
     ]
@@ -3958,6 +4116,7 @@ exports.CSS_PROPERTIES = {
       "repeat-y",
       "repeating-linear-gradient",
       "repeating-radial-gradient",
+      "revert",
       "rgb",
       "rgba",
       "round",
@@ -3980,6 +4139,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "local",
+      "revert",
       "scroll",
       "unset"
     ]
@@ -4006,6 +4166,7 @@ exports.CSS_PROPERTIES = {
       "multiply",
       "normal",
       "overlay",
+      "revert",
       "saturation",
       "screen",
       "soft-light",
@@ -4024,6 +4185,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "padding-box",
+      "revert",
       "text",
       "unset"
     ]
@@ -4043,6 +4205,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -4073,6 +4236,7 @@ exports.CSS_PROPERTIES = {
       "radial-gradient",
       "repeating-linear-gradient",
       "repeating-radial-gradient",
+      "revert",
       "unset",
       "url"
     ]
@@ -4089,6 +4253,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "padding-box",
+      "revert",
       "unset"
     ]
   },
@@ -4105,6 +4270,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -4120,6 +4286,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -4135,6 +4302,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -4151,6 +4319,7 @@ exports.CSS_PROPERTIES = {
       "repeat",
       "repeat-x",
       "repeat-y",
+      "revert",
       "round",
       "space",
       "unset"
@@ -4168,6 +4337,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -4186,6 +4356,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -4246,6 +4417,7 @@ exports.CSS_PROPERTIES = {
       "radial-gradient",
       "repeating-linear-gradient",
       "repeating-radial-gradient",
+      "revert",
       "rgb",
       "rgba",
       "ridge",
@@ -4286,6 +4458,7 @@ exports.CSS_PROPERTIES = {
       "medium",
       "none",
       "outset",
+      "revert",
       "rgb",
       "rgba",
       "ridge",
@@ -4311,6 +4484,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -4334,6 +4508,7 @@ exports.CSS_PROPERTIES = {
       "inset",
       "none",
       "outset",
+      "revert",
       "ridge",
       "solid",
       "unset"
@@ -4353,6 +4528,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "thick",
       "thin",
       "unset"
@@ -4387,6 +4563,7 @@ exports.CSS_PROPERTIES = {
       "medium",
       "none",
       "outset",
+      "revert",
       "rgb",
       "rgba",
       "ridge",
@@ -4412,6 +4589,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -4435,6 +4613,7 @@ exports.CSS_PROPERTIES = {
       "inset",
       "none",
       "outset",
+      "revert",
       "ridge",
       "solid",
       "unset"
@@ -4454,6 +4633,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "thick",
       "thin",
       "unset"
@@ -4488,6 +4668,7 @@ exports.CSS_PROPERTIES = {
       "medium",
       "none",
       "outset",
+      "revert",
       "rgb",
       "rgba",
       "ridge",
@@ -4513,6 +4694,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -4531,6 +4713,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -4546,6 +4729,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -4566,6 +4750,7 @@ exports.CSS_PROPERTIES = {
       "inset",
       "none",
       "outset",
+      "revert",
       "ridge",
       "solid",
       "unset"
@@ -4585,6 +4770,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "thick",
       "thin",
       "unset"
@@ -4600,6 +4786,7 @@ exports.CSS_PROPERTIES = {
       "collapse",
       "inherit",
       "initial",
+      "revert",
       "separate",
       "unset"
     ]
@@ -4622,6 +4809,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -4659,6 +4847,7 @@ exports.CSS_PROPERTIES = {
       "radial-gradient",
       "repeating-linear-gradient",
       "repeating-radial-gradient",
+      "revert",
       "unset",
       "url"
     ]
@@ -4675,6 +4864,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -4687,6 +4877,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -4702,6 +4893,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -4729,6 +4921,7 @@ exports.CSS_PROPERTIES = {
       "radial-gradient",
       "repeating-linear-gradient",
       "repeating-radial-gradient",
+      "revert",
       "unset",
       "url"
     ]
@@ -4746,6 +4939,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -4778,6 +4972,7 @@ exports.CSS_PROPERTIES = {
       "medium",
       "none",
       "outset",
+      "revert",
       "rgb",
       "rgba",
       "ridge",
@@ -4803,6 +4998,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -4826,6 +5022,7 @@ exports.CSS_PROPERTIES = {
       "inset",
       "none",
       "outset",
+      "revert",
       "ridge",
       "solid",
       "unset"
@@ -4845,6 +5042,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "thick",
       "thin",
       "unset"
@@ -4879,6 +5077,7 @@ exports.CSS_PROPERTIES = {
       "medium",
       "none",
       "outset",
+      "revert",
       "rgb",
       "rgba",
       "ridge",
@@ -4904,6 +5103,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -4927,6 +5127,7 @@ exports.CSS_PROPERTIES = {
       "inset",
       "none",
       "outset",
+      "revert",
       "ridge",
       "solid",
       "unset"
@@ -4946,6 +5147,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "thick",
       "thin",
       "unset"
@@ -4980,6 +5182,7 @@ exports.CSS_PROPERTIES = {
       "medium",
       "none",
       "outset",
+      "revert",
       "rgb",
       "rgba",
       "ridge",
@@ -5005,6 +5208,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -5028,6 +5232,7 @@ exports.CSS_PROPERTIES = {
       "inset",
       "none",
       "outset",
+      "revert",
       "ridge",
       "solid",
       "unset"
@@ -5047,6 +5252,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "thick",
       "thin",
       "unset"
@@ -5067,6 +5273,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5099,6 +5306,7 @@ exports.CSS_PROPERTIES = {
       "medium",
       "none",
       "outset",
+      "revert",
       "rgb",
       "rgba",
       "ridge",
@@ -5124,6 +5332,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -5147,6 +5356,7 @@ exports.CSS_PROPERTIES = {
       "inset",
       "none",
       "outset",
+      "revert",
       "ridge",
       "solid",
       "unset"
@@ -5166,6 +5376,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "thick",
       "thin",
       "unset"
@@ -5182,6 +5393,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5205,6 +5417,7 @@ exports.CSS_PROPERTIES = {
       "inset",
       "none",
       "outset",
+      "revert",
       "ridge",
       "solid",
       "unset"
@@ -5239,6 +5452,7 @@ exports.CSS_PROPERTIES = {
       "medium",
       "none",
       "outset",
+      "revert",
       "rgb",
       "rgba",
       "ridge",
@@ -5264,6 +5478,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -5282,6 +5497,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5297,6 +5513,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5317,6 +5534,7 @@ exports.CSS_PROPERTIES = {
       "inset",
       "none",
       "outset",
+      "revert",
       "ridge",
       "solid",
       "unset"
@@ -5336,6 +5554,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "thick",
       "thin",
       "unset"
@@ -5358,6 +5577,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "thick",
       "thin",
       "unset"
@@ -5378,6 +5598,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5391,6 +5612,7 @@ exports.CSS_PROPERTIES = {
       "clone",
       "inherit",
       "initial",
+      "revert",
       "slice",
       "unset"
     ]
@@ -5407,6 +5629,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5421,6 +5644,7 @@ exports.CSS_PROPERTIES = {
       "content-box",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5436,6 +5660,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "left",
+      "revert",
       "right",
       "top",
       "top-outside",
@@ -5458,6 +5683,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -5478,6 +5704,7 @@ exports.CSS_PROPERTIES = {
       "inline-start",
       "left",
       "none",
+      "revert",
       "right",
       "unset"
     ]
@@ -5491,6 +5718,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5505,6 +5733,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5519,6 +5748,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "nonzero",
+      "revert",
       "unset"
     ]
   },
@@ -5537,6 +5767,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -5554,6 +5785,7 @@ exports.CSS_PROPERTIES = {
       "exact",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5568,6 +5800,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "linearrgb",
+      "revert",
       "srgb",
       "unset"
     ]
@@ -5583,6 +5816,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "linearrgb",
+      "revert",
       "srgb",
       "unset"
     ]
@@ -5599,6 +5833,7 @@ exports.CSS_PROPERTIES = {
       "auto",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5613,6 +5848,7 @@ exports.CSS_PROPERTIES = {
       "balance",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5631,6 +5867,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -5663,6 +5900,7 @@ exports.CSS_PROPERTIES = {
       "medium",
       "none",
       "outset",
+      "revert",
       "rgb",
       "rgba",
       "ridge",
@@ -5688,6 +5926,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -5711,6 +5950,7 @@ exports.CSS_PROPERTIES = {
       "inset",
       "none",
       "outset",
+      "revert",
       "ridge",
       "solid",
       "unset"
@@ -5730,6 +5970,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "thick",
       "thin",
       "unset"
@@ -5749,6 +5990,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5768,6 +6010,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5782,6 +6025,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5794,6 +6038,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5806,6 +6051,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5820,6 +6066,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5833,6 +6080,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "ltr",
+      "revert",
       "rtl",
       "unset"
     ]
@@ -5873,6 +6121,7 @@ exports.CSS_PROPERTIES = {
       "inline-table",
       "list-item",
       "none",
+      "revert",
       "ruby",
       "ruby-base",
       "ruby-base-container",
@@ -5908,6 +6157,7 @@ exports.CSS_PROPERTIES = {
       "middle",
       "no-change",
       "reset-size",
+      "revert",
       "text-after-edge",
       "text-before-edge",
       "unset",
@@ -5924,6 +6174,7 @@ exports.CSS_PROPERTIES = {
       "hide",
       "inherit",
       "initial",
+      "revert",
       "show",
       "unset"
     ]
@@ -5940,6 +6191,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5954,6 +6206,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -5968,6 +6221,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "nonzero",
+      "revert",
       "unset"
     ]
   },
@@ -5982,6 +6236,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6008,6 +6263,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "max-content",
       "min-content",
+      "revert",
       "unset"
     ]
   },
@@ -6031,6 +6287,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "max-content",
       "min-content",
+      "revert",
       "unset"
     ]
   },
@@ -6045,6 +6302,7 @@ exports.CSS_PROPERTIES = {
       "column-reverse",
       "inherit",
       "initial",
+      "revert",
       "row",
       "row-reverse",
       "unset"
@@ -6063,6 +6321,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "nowrap",
+      "revert",
       "row",
       "row-reverse",
       "unset",
@@ -6081,6 +6340,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6095,6 +6355,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6108,6 +6369,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "nowrap",
+      "revert",
       "unset",
       "wrap",
       "wrap-reverse"
@@ -6126,6 +6388,7 @@ exports.CSS_PROPERTIES = {
       "inline-start",
       "left",
       "none",
+      "revert",
       "right",
       "unset"
     ]
@@ -6145,6 +6408,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -6162,6 +6426,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6213,6 +6478,7 @@ exports.CSS_PROPERTIES = {
       "normal",
       "oblique",
       "petite-caps",
+      "revert",
       "semi-condensed",
       "semi-expanded",
       "small",
@@ -6240,6 +6506,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6252,6 +6519,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6267,6 +6535,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "none",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -6280,6 +6549,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -6300,6 +6570,7 @@ exports.CSS_PROPERTIES = {
       "large",
       "larger",
       "medium",
+      "revert",
       "small",
       "smaller",
       "unset",
@@ -6321,6 +6592,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -6338,6 +6610,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "semi-condensed",
       "semi-expanded",
       "ultra-condensed",
@@ -6357,6 +6630,7 @@ exports.CSS_PROPERTIES = {
       "italic",
       "normal",
       "oblique",
+      "revert",
       "unset"
     ]
   },
@@ -6369,6 +6643,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6390,6 +6665,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "normal",
       "petite-caps",
+      "revert",
       "small-caps",
       "sub",
       "super",
@@ -6407,6 +6683,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6423,6 +6700,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "normal",
       "petite-caps",
+      "revert",
       "small-caps",
       "titling-caps",
       "unicase",
@@ -6438,6 +6716,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6450,6 +6729,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6462,6 +6742,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6475,6 +6756,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "sub",
       "super",
       "unset"
@@ -6489,6 +6771,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6503,6 +6786,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6522,6 +6806,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -6542,6 +6827,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6559,6 +6845,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6574,6 +6861,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6586,6 +6874,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6601,6 +6890,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6616,6 +6906,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6630,6 +6921,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6648,6 +6940,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -6662,6 +6955,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6681,6 +6975,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -6696,6 +6991,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6710,6 +7006,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6728,6 +7025,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -6742,6 +7040,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6759,6 +7058,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6771,6 +7071,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6786,6 +7087,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6801,6 +7103,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6823,6 +7126,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "max-content",
       "min-content",
+      "revert",
       "unset"
     ]
   },
@@ -6838,6 +7142,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "manual",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -6852,6 +7157,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6870,6 +7176,7 @@ exports.CSS_PROPERTIES = {
       "optimizequality",
       "optimizespeed",
       "pixelated",
+      "revert",
       "smooth",
       "unset"
     ]
@@ -6888,6 +7195,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -6910,6 +7218,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "max-content",
       "min-content",
+      "revert",
       "unset"
     ]
   },
@@ -6931,6 +7240,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6949,6 +7259,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6967,6 +7278,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -6985,6 +7297,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7003,6 +7316,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7017,6 +7331,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "isolate",
+      "revert",
       "unset"
     ]
   },
@@ -7037,6 +7352,7 @@ exports.CSS_PROPERTIES = {
       "last baseline",
       "left",
       "normal",
+      "revert",
       "right",
       "space-around",
       "space-between",
@@ -7064,6 +7380,7 @@ exports.CSS_PROPERTIES = {
       "last baseline",
       "left",
       "normal",
+      "revert",
       "right",
       "self-end",
       "self-start",
@@ -7090,6 +7407,7 @@ exports.CSS_PROPERTIES = {
       "last baseline",
       "left",
       "normal",
+      "revert",
       "right",
       "self-end",
       "self-start",
@@ -7113,6 +7431,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7130,6 +7449,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -7148,6 +7468,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -7171,6 +7492,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -7190,6 +7512,7 @@ exports.CSS_PROPERTIES = {
       "inside",
       "none",
       "outside",
+      "revert",
       "unset",
       "url"
     ]
@@ -7206,6 +7529,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset",
       "url"
     ]
@@ -7221,6 +7545,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "inside",
       "outside",
+      "revert",
       "unset"
     ]
   },
@@ -7233,6 +7558,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7254,6 +7580,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7273,6 +7600,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7291,6 +7619,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7309,6 +7638,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7327,6 +7657,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7346,6 +7677,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7364,6 +7696,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7382,6 +7715,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7400,6 +7734,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7418,6 +7753,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7436,6 +7772,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7453,6 +7790,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset",
       "url"
     ]
@@ -7469,6 +7807,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset",
       "url"
     ]
@@ -7485,6 +7824,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset",
       "url"
     ]
@@ -7501,6 +7841,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset",
       "url"
     ]
@@ -7554,6 +7895,7 @@ exports.CSS_PROPERTIES = {
       "repeat-y",
       "repeating-linear-gradient",
       "repeating-radial-gradient",
+      "revert",
       "round",
       "space",
       "stroke-box",
@@ -7577,6 +7919,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "no-clip",
       "padding-box",
+      "revert",
       "stroke-box",
       "unset",
       "view-box"
@@ -7594,6 +7937,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "intersect",
+      "revert",
       "subtract",
       "unset"
     ]
@@ -7622,6 +7966,7 @@ exports.CSS_PROPERTIES = {
       "radial-gradient",
       "repeating-linear-gradient",
       "repeating-radial-gradient",
+      "revert",
       "unset",
       "url"
     ]
@@ -7638,6 +7983,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "luminance",
       "match-source",
+      "revert",
       "unset"
     ]
   },
@@ -7654,6 +8000,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "padding-box",
+      "revert",
       "stroke-box",
       "unset",
       "view-box"
@@ -7672,6 +8019,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7687,6 +8035,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7702,6 +8051,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7718,6 +8068,7 @@ exports.CSS_PROPERTIES = {
       "repeat",
       "repeat-x",
       "repeat-y",
+      "revert",
       "round",
       "space",
       "unset"
@@ -7735,6 +8086,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7749,6 +8101,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "luminance",
+      "revert",
       "unset"
     ]
   },
@@ -7767,6 +8120,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -7789,6 +8143,7 @@ exports.CSS_PROPERTIES = {
       "max-content",
       "min-content",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -7811,6 +8166,7 @@ exports.CSS_PROPERTIES = {
       "max-content",
       "min-content",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -7833,6 +8189,7 @@ exports.CSS_PROPERTIES = {
       "max-content",
       "min-content",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -7851,6 +8208,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7873,6 +8231,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "max-content",
       "min-content",
+      "revert",
       "unset"
     ]
   },
@@ -7895,6 +8254,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "max-content",
       "min-content",
+      "revert",
       "unset"
     ]
   },
@@ -7917,6 +8277,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "max-content",
       "min-content",
+      "revert",
       "unset"
     ]
   },
@@ -7942,6 +8303,7 @@ exports.CSS_PROPERTIES = {
       "multiply",
       "normal",
       "overlay",
+      "revert",
       "saturation",
       "screen",
       "soft-light",
@@ -7961,6 +8323,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "scale-down",
       "unset"
     ]
@@ -7977,6 +8340,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -7995,6 +8359,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8013,6 +8378,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8031,6 +8397,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8049,6 +8416,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8063,6 +8431,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8077,6 +8446,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8109,6 +8479,7 @@ exports.CSS_PROPERTIES = {
       "medium",
       "none",
       "outset",
+      "revert",
       "rgb",
       "rgba",
       "ridge",
@@ -8134,6 +8505,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -8153,6 +8525,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8173,6 +8546,7 @@ exports.CSS_PROPERTIES = {
       "inset",
       "none",
       "outset",
+      "revert",
       "ridge",
       "solid",
       "unset"
@@ -8192,6 +8566,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "medium",
+      "revert",
       "thick",
       "thin",
       "unset"
@@ -8210,6 +8585,7 @@ exports.CSS_PROPERTIES = {
       "hidden",
       "inherit",
       "initial",
+      "revert",
       "scroll",
       "unset",
       "visible"
@@ -8227,6 +8603,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -8242,6 +8619,7 @@ exports.CSS_PROPERTIES = {
       "hidden",
       "inherit",
       "initial",
+      "revert",
       "scroll",
       "unset",
       "visible"
@@ -8259,6 +8637,7 @@ exports.CSS_PROPERTIES = {
       "hidden",
       "inherit",
       "initial",
+      "revert",
       "scroll",
       "unset",
       "visible"
@@ -8281,6 +8660,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8299,6 +8679,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8316,6 +8697,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8333,6 +8715,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8350,6 +8733,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8368,6 +8752,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8385,6 +8770,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8402,6 +8788,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8419,6 +8806,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8436,6 +8824,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8453,6 +8842,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8469,6 +8859,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "left",
+      "revert",
       "right",
       "unset"
     ]
@@ -8486,6 +8877,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "left",
+      "revert",
       "right",
       "unset"
     ]
@@ -8501,6 +8893,7 @@ exports.CSS_PROPERTIES = {
       "avoid",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8513,6 +8906,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8528,6 +8922,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -8543,6 +8938,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8564,6 +8960,7 @@ exports.CSS_PROPERTIES = {
       "last baseline",
       "left",
       "normal",
+      "revert",
       "right",
       "space-around",
       "space-between",
@@ -8592,6 +8989,7 @@ exports.CSS_PROPERTIES = {
       "last baseline",
       "left",
       "normal",
+      "revert",
       "right",
       "self-end",
       "self-start",
@@ -8619,6 +9017,7 @@ exports.CSS_PROPERTIES = {
       "last baseline",
       "left",
       "normal",
+      "revert",
       "right",
       "self-end",
       "self-start",
@@ -8641,6 +9040,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "none",
       "painted",
+      "revert",
       "stroke",
       "unset",
       "visible",
@@ -8661,6 +9061,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "relative",
+      "revert",
       "static",
       "sticky",
       "unset"
@@ -8675,6 +9076,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8690,6 +9092,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset",
       "vertical"
     ]
@@ -8709,6 +9112,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8727,6 +9131,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -8740,6 +9145,7 @@ exports.CSS_PROPERTIES = {
       "center",
       "inherit",
       "initial",
+      "revert",
       "space-around",
       "space-between",
       "start",
@@ -8756,6 +9162,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "over",
+      "revert",
       "under",
       "unset"
     ]
@@ -8770,6 +9177,7 @@ exports.CSS_PROPERTIES = {
       "auto",
       "inherit",
       "initial",
+      "revert",
       "smooth",
       "unset"
     ]
@@ -8786,6 +9194,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8801,6 +9210,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8813,6 +9223,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8825,6 +9236,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8841,6 +9253,7 @@ exports.CSS_PROPERTIES = {
       "mandatory",
       "none",
       "proximity",
+      "revert",
       "unset"
     ]
   },
@@ -8856,6 +9269,7 @@ exports.CSS_PROPERTIES = {
       "mandatory",
       "none",
       "proximity",
+      "revert",
       "unset"
     ]
   },
@@ -8871,6 +9285,7 @@ exports.CSS_PROPERTIES = {
       "mandatory",
       "none",
       "proximity",
+      "revert",
       "unset"
     ]
   },
@@ -8885,6 +9300,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "thin",
       "unset"
     ]
@@ -8902,6 +9318,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "optimizespeed",
+      "revert",
       "unset"
     ]
   },
@@ -8920,6 +9337,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -8937,6 +9355,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8952,6 +9371,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8968,6 +9388,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8986,6 +9407,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -8999,6 +9421,7 @@ exports.CSS_PROPERTIES = {
       "butt",
       "inherit",
       "initial",
+      "revert",
       "round",
       "square",
       "unset"
@@ -9015,6 +9438,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "miter",
+      "revert",
       "round",
       "unset"
     ]
@@ -9030,6 +9454,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9044,6 +9469,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9060,6 +9486,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9077,6 +9504,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9091,6 +9519,7 @@ exports.CSS_PROPERTIES = {
       "fixed",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9110,6 +9539,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "justify",
       "left",
+      "revert",
       "right",
       "start",
       "unset"
@@ -9129,6 +9559,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "justify",
       "left",
+      "revert",
       "right",
       "start",
       "unset"
@@ -9145,6 +9576,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "middle",
+      "revert",
       "start",
       "unset"
     ]
@@ -9158,6 +9590,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9182,6 +9615,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "solid",
@@ -9205,6 +9639,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -9220,6 +9655,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9236,6 +9672,7 @@ exports.CSS_PROPERTIES = {
       "double",
       "inherit",
       "initial",
+      "revert",
       "solid",
       "unset",
       "wavy"
@@ -9257,6 +9694,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -9278,6 +9716,7 @@ exports.CSS_PROPERTIES = {
       "hsla",
       "inherit",
       "initial",
+      "revert",
       "rgb",
       "rgba",
       "transparent",
@@ -9293,6 +9732,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9305,6 +9745,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9322,6 +9763,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9339,6 +9781,7 @@ exports.CSS_PROPERTIES = {
       "inter-character",
       "inter-word",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -9352,6 +9795,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "mixed",
+      "revert",
       "sideways",
       "sideways-right",
       "unset",
@@ -9367,6 +9811,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9383,6 +9828,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "optimizelegibility",
       "optimizespeed",
+      "revert",
       "unset"
     ]
   },
@@ -9398,6 +9844,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9414,6 +9861,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "lowercase",
       "none",
+      "revert",
       "unset",
       "uppercase"
     ]
@@ -9433,6 +9881,7 @@ exports.CSS_PROPERTIES = {
       "calc",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9450,6 +9899,7 @@ exports.CSS_PROPERTIES = {
       "none",
       "pan-x",
       "pan-y",
+      "revert",
       "unset"
     ]
   },
@@ -9462,6 +9912,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9476,6 +9927,7 @@ exports.CSS_PROPERTIES = {
       "fill-box",
       "inherit",
       "initial",
+      "revert",
       "unset",
       "view-box"
     ]
@@ -9492,6 +9944,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9506,6 +9959,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "preserve-3d",
+      "revert",
       "unset"
     ]
   },
@@ -9532,6 +9986,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "linear",
       "none",
+      "revert",
       "step-end",
       "step-start",
       "steps",
@@ -9549,6 +10004,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9563,6 +10019,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9577,6 +10034,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -9597,6 +10055,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "linear",
+      "revert",
       "step-end",
       "step-start",
       "steps",
@@ -9621,6 +10080,7 @@ exports.CSS_PROPERTIES = {
       "isolate-override",
       "normal",
       "plaintext",
+      "revert",
       "unset"
     ]
   },
@@ -9635,6 +10095,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "non-scaling-stroke",
       "none",
+      "revert",
       "unset"
     ]
   },
@@ -9656,6 +10117,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "middle",
+      "revert",
       "sub",
       "super",
       "text-bottom",
@@ -9675,6 +10137,7 @@ exports.CSS_PROPERTIES = {
       "hidden",
       "inherit",
       "initial",
+      "revert",
       "unset",
       "visible"
     ]
@@ -9695,6 +10158,7 @@ exports.CSS_PROPERTIES = {
       "pre",
       "pre-line",
       "pre-wrap",
+      "revert",
       "unset"
     ]
   },
@@ -9717,6 +10181,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "max-content",
       "min-content",
+      "revert",
       "unset"
     ]
   },
@@ -9729,6 +10194,7 @@ exports.CSS_PROPERTIES = {
     "values": [
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   },
@@ -9744,6 +10210,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "keep-all",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -9762,6 +10229,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -9777,6 +10245,7 @@ exports.CSS_PROPERTIES = {
       "inherit",
       "initial",
       "normal",
+      "revert",
       "unset"
     ]
   },
@@ -9792,6 +10261,7 @@ exports.CSS_PROPERTIES = {
       "initial",
       "lr",
       "lr-tb",
+      "revert",
       "rl",
       "rl-tb",
       "sideways-lr",
@@ -9815,6 +10285,7 @@ exports.CSS_PROPERTIES = {
       "auto",
       "inherit",
       "initial",
+      "revert",
       "unset"
     ]
   }

From e6b48fcc953c6f02750360cb3942c1df9b714585 Mon Sep 17 00:00:00 2001
From: Jerico <jtsanchez9@up.edu.ph>
Date: Fri, 4 Jul 2025 17:31:53 +0800
Subject: [PATCH 14/20] Issue #2106 - Part 3: Add 'contain' as user-select
 value, retain 'element'

---
 layout/style/nsCSSProps.cpp  | 1 +
 layout/style/nsStyleConsts.h | 1 +
 2 files changed, 2 insertions(+)

diff --git a/layout/style/nsCSSProps.cpp b/layout/style/nsCSSProps.cpp
index 73a8d5dd29..75a81aba00 100644
--- a/layout/style/nsCSSProps.cpp
+++ b/layout/style/nsCSSProps.cpp
@@ -2216,6 +2216,7 @@ const KTableEntry nsCSSProps::kUserSelectKTable[] = {
   { eCSSKeyword_auto,       StyleUserSelect::Auto },
   { eCSSKeyword_text,       StyleUserSelect::Text },
   { eCSSKeyword_element,    StyleUserSelect::Element },
+  { eCSSKeyword_contain,    StyleUserSelect::Contain },
   { eCSSKeyword_elements,   StyleUserSelect::Elements },
   { eCSSKeyword_all,        StyleUserSelect::All },
   { eCSSKeyword_toggle,     StyleUserSelect::Toggle },
diff --git a/layout/style/nsStyleConsts.h b/layout/style/nsStyleConsts.h
index 9507ea6fab..a708a6ff90 100644
--- a/layout/style/nsStyleConsts.h
+++ b/layout/style/nsStyleConsts.h
@@ -186,6 +186,7 @@ enum class StyleUserSelect : uint8_t {
   None,
   Text,
   Element,
+  Contain,
   Elements,
   All,
   Toggle,

From 2d9cb22a2804fa6f93145a55ea1c91dd98659a74 Mon Sep 17 00:00:00 2001
From: Moonchild <moonchild@palemoon.org>
Date: Fri, 4 Jul 2025 22:41:03 +0200
Subject: [PATCH 15/20] [devtools] Further improve special character escaping
 in "copy as curl".

Follow-up to 15335ce39d1ea2ef4585a36a4d562a3894459a15

Trying to cross-platform sanitize causes issues escaping too much and
as a result mangling the curl commands that get spit out.
This reverts previously added Windows-specific escaping on POSIX and
vice versa.
Since we do not offer cross-platform copying as a curl command in devtools
anyway, it makes little sense to sanitize for the O.S. we're not running on
as we would not be using the command processor in such environments that
could trip over characters for the other O.S. This was previously added
as a defense-in-depth in case we would start offering this, but I see no
real reason to do so, anyway.

Also decided to in-line comments for readability instead of a bulleted
list in the function head.

Mozilla has taken similar steps because of fall-out, but they do offer
cross-platform "copy as curl" for corner cases, so they will have to
find solutions for a problem we won't have.
---
 devtools/client/shared/curl.js | 65 ++++++++++++++--------------------
 1 file changed, 27 insertions(+), 38 deletions(-)

diff --git a/devtools/client/shared/curl.js b/devtools/client/shared/curl.js
index 53f24685bf..478d3f1ecd 100644
--- a/devtools/client/shared/curl.js
+++ b/devtools/client/shared/curl.js
@@ -395,9 +395,6 @@ const CurlUtils = {
       return "\\u" + ("0000" + code).substr(code.length, 4);
     }
 
-    // Escape & and |, which are special characters on Windows.
-    const winSpecialCharsRegEx = /([&\|])/g;
-
     if (/[^\x20-\x7E]|\'/.test(str)) {
       // Use ANSI-C quoting syntax.
       return "$\'" + str.replace(/\\/g, "\\\\")
@@ -405,58 +402,50 @@ const CurlUtils = {
                         .replace(/\n/g, "\\n")
                         .replace(/\r/g, "\\r")
                         .replace(/!/g, "\\041")
-                        .replace(winSpecialCharsRegEx, "^$1")
                         .replace(/[^\x20-\x7E]/g, escapeCharacter) + "'";
     }
 
     // Use single quote syntax.
-    return "'" + str.replace(winSpecialCharsRegEx, "^$1") + "'";
+    return "'" + str + "'";
   },
 
   /**
    * Escape util function for Windows systems.
    */
   escapeStringWin: function (str) {
-    /* 
-       Because the cmd.exe parser and the MS Crt arguments parsers use some
-       of the same escape characters, they can interact with each other in
-       terrible ways, meaning the order of operations is critical here.
-
-       1. Replace \ with \\ first, because it is an escape character for
-       certain conditions in both parsers.
-
-       2. Escape double quotes with double backslashes.
-       
-       3. Escape ` and $ so commands do not get executed, e.g $(calc.exe) or
-       `\$(calc.exe)
-       
-       4. Escape all characters we are not sure about with ^, to ensure it
-       gets to the MS Crt arguments parser safely.
-
-       5. The % character is special because the MS Crt arguments parser will
-       try and look for environment variables and fill them in, in-place. We
-       cannot escape them with % and cannot escape them with ^ (because it's
-       cmd.exe's escape, not the MS Crt arguments parser). So, we can get the
-       cmd.exe parser to escape the character after it, if it is followed by
-       a valid starting character of an environment variable.
-       This ensures we do not try and double-escape another ^ if it was placed
-       by the previous replace.
-
-       6. Lastly, we replace new lines with ^ and TWO new lines, because the
-       first new line is there to enact the escape command, and the second is
-       the character to escape (in this case new line).
-    */
-    const encapsChars = '^"';
+    const encapsChars = '"';
     return (
       encapsChars +
       str
+        // Replace \ with \\ first because it is an escape character for certain
+        // conditions in both parsers.
         .replace(/\\/g, "\\\\")
-        .replace(/"/g, '\\"')
+        // Replace double quote chars with two double quotes (not by escaping with \")
+        // because it is recognized by both cmd.exe and MS CRT arguments parser.
+        .replace(/"/g, '""')
+        // Escape ` and $ so commands do not get executed e.g $(calc.exe) or `\$(calc.exe)
         .replace(/[`$]/g, "\\$&")
+        // Then escape all characters we are not sure about with ^ to ensure it
+        // gets to the MS CRT parser safely.
         .replace(/[^a-zA-Z0-9\s_\-:=+~\/.',?;()*\$&\\{}\"`]/g, "^$&")
+        // The % character is special because MS CRT parser will try and look for
+        // ENV variables and fill them in its place. We cannot escape them with %
+        // and cannot escape them with ^ (because it's cmd.exe's escape not MS CRT
+        // parser); So we can get cmd.exe parser to escape the character after it,
+        // if it is followed by a valid beginning character of an ENV variable.
+        // This ensures we do not try and double escape another ^ if it was placed
+        // by the previous replace.
         .replace(/%(?=[a-zA-Z0-9_])/g, "%^")
-        .replace(/\r?\n/g, "^\n\n")
-      + encapsChars);
+        // We replace \r and \r\n with \n, this allows to consistently escape all new
+        // lines in the next replace
+        .replace(/\r\n?/g, "\n")
+        // Lastly we replace new lines with ^ and TWO new lines because the first
+        // new line is there to enact the escape command the second is the character
+        // to escape (in this case new line).
+        // The extra " enables escaping new lines with ^ within quotes in cmd.exe.
+        .replace(/\n/g, '"^\r\n\r\n"')
+      + encapsChars
+    );
   }
 };
 

From 9f7430f8b94061302e49f7c7028b5c81fbc961d6 Mon Sep 17 00:00:00 2001
From: erixreyes <ebreyes2@up.edu.ph>
Date: Sat, 5 Jul 2025 05:38:01 +0800
Subject: [PATCH 16/20] No Issue - Add detection for medium in border shorthand

---
 layout/style/Declaration.cpp | 82 ++++++++++++++++++++++++++++++------
 1 file changed, 68 insertions(+), 14 deletions(-)

diff --git a/layout/style/Declaration.cpp b/layout/style/Declaration.cpp
index f4197439f8..abda70f277 100644
--- a/layout/style/Declaration.cpp
+++ b/layout/style/Declaration.cpp
@@ -802,18 +802,63 @@ Declaration::GetPropertyValueInternal(
       MOZ_ASSERT(StringEndsWith(nsCSSProps::GetStringValue(subprops[2]),
                                 NS_LITERAL_CSTRING("-color")),
                  "third subprop must be the color property");
+
+      const nsCSSValue *widthValue = data->ValueFor(subprops[0]);
+      const nsCSSValue *styleValue = data->ValueFor(subprops[1]);
       const nsCSSValue *colorValue = data->ValueFor(subprops[2]);
+
+      bool isNoneStyle = 
+        styleValue->GetUnit() == eCSSUnit_Enumerated &&
+        styleValue->GetIntValue() == NS_STYLE_BORDER_STYLE_NONE;
+
+      bool isMediumWidth = 
+        widthValue->GetUnit() == eCSSUnit_Enumerated &&
+        widthValue->GetIntValue() == NS_STYLE_BORDER_WIDTH_MEDIUM;
+
+      bool isCurrentColor = colorValue->GetUnit() == eCSSUnit_EnumColor &&
+                            colorValue->GetIntValue() == NS_COLOR_CURRENTCOLOR;
+
+      if (isNoneStyle && isCurrentColor) {
+        // Case (1) above: some subproperties not specified.
+        return;
+      }
+
       bool isCurrentColor =
         colorValue->GetUnit() == eCSSUnit_EnumColor &&
         colorValue->GetIntValue() == NS_COLOR_CURRENTCOLOR;
-      if (!AppendValueToString(subprops[0], aValue, aSerialization) ||
-          !(aValue.Append(char16_t(' ')),
-            AppendValueToString(subprops[1], aValue, aSerialization)) ||
-          // Don't output a third value when it's currentcolor.
-          !(isCurrentColor ||
-            (aValue.Append(char16_t(' ')),
-             AppendValueToString(subprops[2], aValue, aSerialization)))) {
-        aValue.Truncate();
+
+      // special case: if we have just color and all other values are default,
+      // output: color
+      if (!isCurrentColor && isNoneStyle && isMediumWidth) {
+        if (!AppendValueToString(subprops[2], aValue, aSerialization)) {
+          aValue.Truncate();
+        }
+        break;
+      }
+
+      // normal case: output width unless medium and only have color
+      if (!(isMediumWidth && isNoneStyle && !isCurrentColor)) {
+        if (!AppendValueToString(subprops[0], aValue, aSerialization)) {
+          aValue.Truncate();
+          break;
+        }
+      }
+
+      // if style is not none, append style
+      if (!isNoneStyle) {
+        aValue.Append(char16_t(' '));
+        if (!AppendValueToString(subprops[1], aValue, aSerialization)) {
+          aValue.Truncate();
+          break;
+        }
+      }
+
+      if (!isCurrentColor) {
+        aValue.Append(char16_t(' '));
+        if (!AppendValueToString(subprops[2], aValue, aSerialization)) {
+          aValue.Truncate();
+          break;
+        }
       }
       break;
     }
@@ -1030,12 +1075,21 @@ Declaration::GetPropertyValueInternal(
                           aSerialization);
       break;
     case eCSSProperty_overflow: {
-      const nsCSSValue &xValue =
-        *data->ValueFor(eCSSProperty_overflow_x);
-      const nsCSSValue &yValue =
-        *data->ValueFor(eCSSProperty_overflow_y);
-      if (xValue == yValue)
-        xValue.AppendToString(eCSSProperty_overflow_x, aValue, aSerialization);
+      const nsCSSValue* xValue = data->ValueFor(eCSSProperty_overflow_x);
+      const nsCSSValue* yValue = data->ValueFor(eCSSProperty_overflow_y);
+      if (!xValue || !yValue ||
+          xValue->GetUnit() != eCSSUnit_Enumerated ||
+          yValue->GetUnit() != eCSSUnit_Enumerated) {
+        aValue.Truncate(); // don't serialize shorthand if not both present/enumerated
+        break;
+      }
+      if (*xValue == *yValue) {
+        xValue->AppendToString(eCSSProperty_overflow_x, aValue, aSerialization);
+      } else {
+        xValue->AppendToString(eCSSProperty_overflow_x, aValue, aSerialization);
+        aValue.Append(char16_t(' '));
+        yValue->AppendToString(eCSSProperty_overflow_y, aValue, aSerialization);
+      }
       break;
     }
     case eCSSProperty_text_decoration: {

From f4ffb1ec1620677ed88bcf5b48fc1eda1aaafdc2 Mon Sep 17 00:00:00 2001
From: erixreyes <ebreyes2@up.edu.ph>
Date: Sat, 5 Jul 2025 05:39:25 +0800
Subject: [PATCH 17/20] Issue #2124 - Adjust overflow parser to handle two
 values

---
 layout/style/nsCSSParser.cpp | 46 ++++++++++++++++++++++++------------
 1 file changed, 31 insertions(+), 15 deletions(-)

diff --git a/layout/style/nsCSSParser.cpp b/layout/style/nsCSSParser.cpp
index e8078eaf9d..e1b01a4543 100644
--- a/layout/style/nsCSSParser.cpp
+++ b/layout/style/nsCSSParser.cpp
@@ -15847,25 +15847,41 @@ CSSParserImpl::ParseOutline()
 bool
 CSSParserImpl::ParseOverflow()
 {
-  nsCSSValue overflow;
-  if (!ParseSingleTokenVariant(overflow, VARIANT_HK,
-                               nsCSSProps::kOverflowKTable)) {
+  nsCSSValue overflowX, overflowY;
+  // Parse the first value
+  if (!ParseSingleTokenVariant(overflowX, VARIANT_HK, nsCSSProps::kOverflowKTable)) {
     return false;
   }
 
-  nsCSSValue overflowX(overflow);
-  nsCSSValue overflowY(overflow);
-  if (eCSSUnit_Enumerated == overflow.GetUnit())
-    switch(overflow.GetIntValue()) {
-      case NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL:
-        overflowX.SetIntValue(NS_STYLE_OVERFLOW_SCROLL, eCSSUnit_Enumerated);
-        overflowY.SetIntValue(NS_STYLE_OVERFLOW_HIDDEN, eCSSUnit_Enumerated);
-        break;
-      case NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL:
-        overflowX.SetIntValue(NS_STYLE_OVERFLOW_HIDDEN, eCSSUnit_Enumerated);
-        overflowY.SetIntValue(NS_STYLE_OVERFLOW_SCROLL, eCSSUnit_Enumerated);
-        break;
+  // Try to parse a second value (optional)
+  bool haveSecond = ParseSingleTokenVariant(overflowY, VARIANT_HK, nsCSSProps::kOverflowKTable);
+  if (!haveSecond) {
+    overflowY = overflowX;
+  }
+
+  // Handle legacy scrollbars keywords for each axis
+  auto fix_legacy = [](nsCSSValue& v, bool isX) {
+    if (v.GetUnit() == eCSSUnit_Enumerated) {
+      switch (v.GetIntValue()) {
+        case NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL:
+          if (isX) {
+            v.SetIntValue(NS_STYLE_OVERFLOW_SCROLL, eCSSUnit_Enumerated);
+          } else {
+            v.SetIntValue(NS_STYLE_OVERFLOW_HIDDEN, eCSSUnit_Enumerated);
+          }
+          break;
+        case NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL:
+          if (isX) {
+            v.SetIntValue(NS_STYLE_OVERFLOW_HIDDEN, eCSSUnit_Enumerated);
+          } else {
+            v.SetIntValue(NS_STYLE_OVERFLOW_SCROLL, eCSSUnit_Enumerated);
+          }
+          break;
+      }
     }
+  };
+  fix_legacy(overflowX, true);
+  fix_legacy(overflowY, false);
   AppendValue(eCSSProperty_overflow_x, overflowX);
   AppendValue(eCSSProperty_overflow_y, overflowY);
   return true;

From 7c52fd934f346b8a9c5bf692c8c838af2ad9e0f5 Mon Sep 17 00:00:00 2001
From: erixreyes <ebreyes2@up.edu.ph>
Date: Sat, 5 Jul 2025 05:41:47 +0800
Subject: [PATCH 18/20] Issue #2662 - Implement axis-shorthand parsing

---
 layout/style/nsCSSPropLogicalGroupList.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/layout/style/nsCSSPropLogicalGroupList.h b/layout/style/nsCSSPropLogicalGroupList.h
index 3d8a52bc90..81dbee641d 100644
--- a/layout/style/nsCSSPropLogicalGroupList.h
+++ b/layout/style/nsCSSPropLogicalGroupList.h
@@ -54,3 +54,4 @@ CSS_PROP_LOGICAL_GROUP_BOX(Offset)
 CSS_PROP_LOGICAL_GROUP_SHORTHAND(Padding)
 CSS_PROP_LOGICAL_GROUP_AXIS(MinSize)
 CSS_PROP_LOGICAL_GROUP_AXIS(Size)
+CSS_PROP_LOGICAL_GROUP_AXIS(Overflow)
\ No newline at end of file

From 7626c99cebc2104c294b1f5fce843093848c24fb Mon Sep 17 00:00:00 2001
From: erixreyes <ebreyes2@up.edu.ph>
Date: Sat, 5 Jul 2025 05:47:31 +0800
Subject: [PATCH 19/20] Issue #2124/2662: Optimize overflow shorthand parsing
 and serialization

---
 layout/style/nsCSSProps.cpp         |  7 +++++++
 layout/style/nsComputedDOMStyle.cpp | 23 +++++++++++++++++------
 2 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/layout/style/nsCSSProps.cpp b/layout/style/nsCSSProps.cpp
index 75a81aba00..3b4eeac49f 100644
--- a/layout/style/nsCSSProps.cpp
+++ b/layout/style/nsCSSProps.cpp
@@ -3181,6 +3181,13 @@ static const nsCSSPropertyID gSizeLogicalGroupTable[] = {
   eCSSProperty_UNKNOWN
 };
 
+
+static const nsCSSPropertyID gOverflowLogicalGroupTable[] = {
+  eCSSProperty_overflow_y,
+  eCSSProperty_overflow_x,
+  eCSSProperty_UNKNOWN
+};
+
 const nsCSSPropertyID* const
 nsCSSProps::kLogicalGroupTable[eCSSPropertyLogicalGroup_COUNT] = {
 #define CSS_PROP_LOGICAL_GROUP_SHORTHAND(id_) g##id_##SubpropTable,
diff --git a/layout/style/nsComputedDOMStyle.cpp b/layout/style/nsComputedDOMStyle.cpp
index 357df17662..38b61379dc 100644
--- a/layout/style/nsComputedDOMStyle.cpp
+++ b/layout/style/nsComputedDOMStyle.cpp
@@ -4750,15 +4750,26 @@ nsComputedDOMStyle::DoGetOverflow()
 {
   const nsStyleDisplay* display = StyleDisplay();
 
-  if (display->mOverflowX != display->mOverflowY) {
-    // No value to return.  We can't express this combination of
-    // values as a shorthand.
-    return nullptr;
+  if (display->mOverflowX == display->mOverflowY) {
+    RefPtr<nsROCSSPrimitiveValue> val = new nsROCSSPrimitiveValue;
+    val->SetIdent(nsCSSProps::ValueToKeywordEnum(display->mOverflowX,
+                                                 nsCSSProps::kOverflowKTable));
+    return val.forget();
   }
 
   RefPtr<nsROCSSPrimitiveValue> val = new nsROCSSPrimitiveValue;
-  val->SetIdent(nsCSSProps::ValueToKeywordEnum(display->mOverflowX,
-                                               nsCSSProps::kOverflowKTable));
+  nsAutoString result;
+  
+  nsCSSKeyword xKeyword = nsCSSProps::ValueToKeywordEnum(display->mOverflowX,
+                                                         nsCSSProps::kOverflowKTable);
+  nsCSSKeyword yKeyword = nsCSSProps::ValueToKeywordEnum(display->mOverflowY,
+                                                         nsCSSProps::kOverflowKTable);
+  
+  result.AppendASCII(nsCSSKeywords::GetStringValue(xKeyword).get());
+  result.Append(char16_t(' '));
+  result.AppendASCII(nsCSSKeywords::GetStringValue(yKeyword).get());
+  
+  val->SetString(result);
   return val.forget();
 }
 

From dae72b452cd3c4f30311a0b3994d0102d93d401d Mon Sep 17 00:00:00 2001
From: MeladJM <jcmelad@up.edu.ph>
Date: Sat, 5 Jul 2025 22:22:57 +0800
Subject: [PATCH 20/20] Issue #2124/2662: Cleaning of code

---
 layout/style/Declaration.cpp | 2 +-
 layout/style/nsRuleNode.cpp  | 8 --------
 2 files changed, 1 insertion(+), 9 deletions(-)

diff --git a/layout/style/Declaration.cpp b/layout/style/Declaration.cpp
index abda70f277..8638b91071 100644
--- a/layout/style/Declaration.cpp
+++ b/layout/style/Declaration.cpp
@@ -823,7 +823,7 @@ Declaration::GetPropertyValueInternal(
         return;
       }
 
-      bool isCurrentColor =
+      isCurrentColor =
         colorValue->GetUnit() == eCSSUnit_EnumColor &&
         colorValue->GetIntValue() == NS_COLOR_CURRENTCOLOR;
 
diff --git a/layout/style/nsRuleNode.cpp b/layout/style/nsRuleNode.cpp
index 33c8ad5fa4..27f3e6f5f5 100644
--- a/layout/style/nsRuleNode.cpp
+++ b/layout/style/nsRuleNode.cpp
@@ -6427,14 +6427,6 @@ nsRuleNode::ComputeDisplayData(void* aStartStruct,
       display->mOverflowY = NS_STYLE_OVERFLOW_HIDDEN;
     }
 
-    // If 'visible' is specified but doesn't match the other dimension, it
-    // turns into 'auto'.
-    if (display->mOverflowX == NS_STYLE_OVERFLOW_VISIBLE) {
-      display->mOverflowX = NS_STYLE_OVERFLOW_AUTO;
-    }
-    if (display->mOverflowY == NS_STYLE_OVERFLOW_VISIBLE) {
-      display->mOverflowY = NS_STYLE_OVERFLOW_AUTO;
-    }
   }
 
   // When 'contain: paint', update overflow from 'visible' to 'clip'.