diff --git a/devtools/shared/css/generated/properties-db.js b/devtools/shared/css/generated/properties-db.js
index a8a97cfa7c..96a1322fae 100644
--- a/devtools/shared/css/generated/properties-db.js
+++ b/devtools/shared/css/generated/properties-db.js
@@ -2978,6 +2978,7 @@ exports.CSS_PROPERTIES = {
       "-moz-text",
       "all",
       "auto",
+      "contain",
       "element",
       "elements",
       "inherit",
@@ -10072,6 +10073,7 @@ exports.CSS_PROPERTIES = {
       "-moz-text",
       "all",
       "auto",
+      "contain",
       "element",
       "elements",
       "inherit",
diff --git a/layout/style/test/property_database.js b/layout/style/test/property_database.js
index f8d6a3dc64..368b476e64 100644
--- a/layout/style/test/property_database.js
+++ b/layout/style/test/property_database.js
@@ -2242,7 +2242,7 @@ var gCSSProperties = {
     inherited: false,
     type: CSS_TYPE_LONGHAND,
     initial_values: [ "auto" ],
-    other_values: [ "none", "text", "element", "elements", "all", "toggle", "tri-state", "-moz-all", "-moz-none" ],
+    other_values: [ "none", "text", "element", "contain", "elements", "all", "toggle", "tri-state", "-moz-all", "-moz-none" ],
     invalid_values: []
   },
   "background": {