Issue #1757 - Reinstate "dom.details_element.enabled" preference

The removal of this preference was botched, all other surrounding plumbing changes appear to be working okay. The ability to use prefs to control this stylesheet might be useful in the future, so perhaps this is one of those "if it ain't broke, don't fix it" bugs where leaving well enough alone in the first place would have been the best choice.
2026-09-08 16:58:38 +09:00 · 2021-03-31 17:57:48 -05:00 · 2021-03-31 17:57:48 -05:00 · 618fa768c8
commit 618fa768c8
parent be539ad8fc
15 changed files with 111 additions and 19 deletions
--- a/layout/base/nsCSSFrameConstructor.cpp
+++ b/layout/base/nsCSSFrameConstructor.cpp
@ -3580,6 +3580,10 @@ nsCSSFrameConstructor::FindHTMLData(Element* aElement,
    return nullptr;
  }

+  if (aTag == nsGkAtoms::details && !HTMLDetailsElement::IsDetailsEnabled()) {
+    return nullptr;
+  }
+
  static const FrameConstructionDataByTag sHTMLData[] = {
    SIMPLE_TAG_CHAIN(img, nsCSSFrameConstructor::FindImgData),
    SIMPLE_TAG_CHAIN(mozgeneratedcontentimage,
@ -5791,7 +5795,7 @@ nsCSSFrameConstructor::AddFrameConstructionItemsInternal(nsFrameConstructorState
  // ::before and ::after); we always want to create "internal" anonymous
  // content.
  auto* details = HTMLDetailsElement::FromContentOrNull(parent);
-  if (details && !details->Open() &&
+  if (details && details->IsDetailsEnabled() && !details->Open() &&
      (!aContent->IsRootOfNativeAnonymousSubtree() ||
       aContent->IsGeneratedContentContainerForBefore() ||
       aContent->IsGeneratedContentContainerForAfter())) {
@ -5959,7 +5963,7 @@ nsCSSFrameConstructor::AddFrameConstructionItemsInternal(nsFrameConstructorState
  }

  FrameConstructionItem* item = nullptr;
-  if (details && details->Open()) {
+  if (details && details->IsDetailsEnabled() && details->Open()) {
    auto* summary = HTMLSummaryElement::FromContentOrNull(aContent);
    if (summary && summary->IsMainSummary()) {
      // If details is open, the main summary needs to be rendered as if it is
--- a/layout/generic/crashtests/crashtests.list
+++ b/layout/generic/crashtests/crashtests.list
@ -606,19 +606,19 @@ pref(layout.css.grid.enabled,true) load 1225376.html
 pref(layout.css.grid.enabled,true) load 1225592.html
 load 1229437-1.html
 load 1229437-2.html
-load details-containing-only-text.html
-load details-display-none-summary-1.html
-load details-display-none-summary-2.html
-load details-display-none-summary-3.html
-load details-open-overflow-auto.html
-load details-open-overflow-hidden.html
-load details-three-columns.html
+pref(dom.details_element.enabled,true) load details-containing-only-text.html
+pref(dom.details_element.enabled,true) load details-display-none-summary-1.html
+pref(dom.details_element.enabled,true) load details-display-none-summary-2.html
+pref(dom.details_element.enabled,true) load details-display-none-summary-3.html
+pref(dom.details_element.enabled,true) load details-open-overflow-auto.html
+pref(dom.details_element.enabled,true) load details-open-overflow-hidden.html
+pref(dom.details_element.enabled,true) load details-three-columns.html
 load first-letter-638937-1.html
 load first-letter-638937-2.html
 load flex-nested-abspos-1.html
 pref(dom.meta-viewport.enabled,true) test-pref(font.size.inflation.emPerLine,15) asserts(0-100) load font-inflation-762332.html # bug 762332
 load outline-on-frameset.xhtml
-load summary-position-out-of-flow.html
+pref(dom.details_element.enabled,true) load summary-position-out-of-flow.html
 load text-overflow-bug666751-1.html
 load text-overflow-bug666751-2.html
 load text-overflow-bug670564.xhtml
--- a/layout/generic/nsContainerFrame.cpp
+++ b/layout/generic/nsContainerFrame.cpp
@ -1891,10 +1891,12 @@ nsContainerFrame::RenumberFrameAndDescendants(int32_t* aOrdinal,
  }

  // Do not renumber list for summary elements.
-  HTMLSummaryElement* summary =
-    HTMLSummaryElement::FromContent(kid->GetContent());
-  if (summary && summary->IsMainSummary()) {
-    return false;
+  if (HTMLDetailsElement::IsDetailsEnabled()) {
+    HTMLSummaryElement* summary =
+      HTMLSummaryElement::FromContent(kid->GetContent());
+    if (summary && summary->IsMainSummary()) {
+      return false;
+    }
  }

  bool kidRenumberedABullet = false;
--- a/layout/reftests/details-summary/disabled-no-summary-ref.html
+++ b/layout/reftests/details-summary/disabled-no-summary-ref.html
@ -0,0 +1,11 @@
+<!DOCTYPE html>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<html>
+  <body>
+    <div>
+      <p>This is the details.</p>
+    </div>
+  </body>
+</html>
--- a/layout/reftests/details-summary/disabled-single-summary-ref.html
+++ b/layout/reftests/details-summary/disabled-single-summary-ref.html
@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<html>
+  <body>
+    <div>
+      <div>Summary</div>
+      <p>This is the details.</p>
+    </div>
+  </body>
+</html>
--- a/layout/reftests/details-summary/reftest.list
+++ b/layout/reftests/details-summary/reftest.list
@ -1,3 +1,10 @@
+default-preferences pref(dom.details_element.enabled,true)
+
+# Disable <details> and <summary>
+pref(dom.details_element.enabled,false) == single-summary.html disabled-single-summary-ref.html
+pref(dom.details_element.enabled,false) == open-single-summary.html disabled-single-summary-ref.html
+pref(dom.details_element.enabled,false) == no-summary.html disabled-no-summary-ref.html
+
 # Basic <summary> handling
 == multiple-summary.html single-summary.html
 == open-multiple-summary.html open-multiple-summary-ref.html
--- a/layout/style/nsLayoutStylesheetCache.cpp
+++ b/layout/style/nsLayoutStylesheetCache.cpp
@ -121,6 +121,11 @@ nsLayoutStylesheetCache::UASheet()
 StyleSheet*
 nsLayoutStylesheetCache::HTMLSheet()
 {
+  if (!mHTMLSheet) {
+    LoadSheetURL("resource://gre-resources/html.css",
+                 &mHTMLSheet, eAgentSheetFeatures, eCrash);
+  }
+
  return mHTMLSheet;
 }

@ -316,8 +321,6 @@ nsLayoutStylesheetCache::nsLayoutStylesheetCache(StyleBackendType aType)
  // per-profile, since they're profile-invariant.
  LoadSheetURL("resource://gre-resources/counterstyles.css",
               &mCounterStylesSheet, eAgentSheetFeatures, eCrash);
-  LoadSheetURL("resource://gre-resources/html.css",
-               &mHTMLSheet, eAgentSheetFeatures, eCrash);
  LoadSheetURL("chrome://global/content/minimal-xul.css",
               &mMinimalXULSheet, eAgentSheetFeatures, eCrash);
  LoadSheetURL("resource://gre-resources/quirk.css",
@ -378,6 +381,8 @@ nsLayoutStylesheetCache::For(StyleBackendType aType)
    //                               "layout.css.example-pref.enabled");
    Preferences::RegisterCallback(&DependentPrefChanged,
                                  "layout.css.grid.enabled");
+    Preferences::RegisterCallback(&DependentPrefChanged,
+                                  "dom.details_element.enabled");
  }

  return cache;
@ -549,6 +554,7 @@ nsLayoutStylesheetCache::DependentPrefChanged(const char* aPref, void* aData)
                  gStyleCache_Servo ? &gStyleCache_Servo->sheet_ : nullptr);

  INVALIDATE(mUASheet);  // for layout.css.grid.enabled
+  INVALIDATE(mHTMLSheet); // for dom.details_element.enabled

 #undef INVALIDATE
 }