diff --git a/devtools/shared/css/generated/properties-db.js b/devtools/shared/css/generated/properties-db.js
index 8edba444e3e4..b4963e3f1d84 100644
--- a/devtools/shared/css/generated/properties-db.js
+++ b/devtools/shared/css/generated/properties-db.js
@@ -9859,78 +9859,6 @@ exports.PREFERENCES = [
     "font-variation-settings",
     "layout.css.font-variations.enabled"
   ],
-  [
-    "grid",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-area",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-auto-columns",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-auto-flow",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-auto-rows",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-column",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-column-end",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-column-gap",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-column-start",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-gap",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-row",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-row-end",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-row-gap",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-row-start",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-template",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-template-areas",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-template-columns",
-    "layout.css.grid.enabled"
-  ],
-  [
-    "grid-template-rows",
-    "layout.css.grid.enabled"
-  ],
   [
     "initial-letter",
     "layout.css.initial-letter.enabled"
diff --git a/layout/base/crashtests/1156588.html b/layout/base/crashtests/1156588.html
index ed0098f79ad3..b48bc3af253a 100644
--- a/layout/base/crashtests/1156588.html
+++ b/layout/base/crashtests/1156588.html
@@ -2,9 +2,6 @@
 <html>
 <head>
 <meta charset="UTF-8">
-<!--
-user_pref("layout.css.grid.enabled", true);
--->
 <script>
 
 function boom()
diff --git a/layout/base/crashtests/crashtests.list b/layout/base/crashtests/crashtests.list
index 9742d1e94c94..d827eaa24dcc 100644
--- a/layout/base/crashtests/crashtests.list
+++ b/layout/base/crashtests/crashtests.list
@@ -470,7 +470,7 @@ load 1127198-1.html
 load 1140198.html
 load 1143535.html
 load 1153716.html
-pref(layout.css.grid.enabled,true) load 1156588.html
+load 1156588.html
 load 1162813.xul
 load 1163583.html
 load 1234622-1.html
diff --git a/layout/base/nsLayoutUtils.cpp b/layout/base/nsLayoutUtils.cpp
index 70129bd812a8..6cb3a44b4ebc 100644
--- a/layout/base/nsLayoutUtils.cpp
+++ b/layout/base/nsLayoutUtils.cpp
@@ -160,7 +160,6 @@ using namespace mozilla::layers;
 using namespace mozilla::layout;
 using namespace mozilla::gfx;
 
-#define GRID_ENABLED_PREF_NAME "layout.css.grid.enabled"
 #define WEBKIT_PREFIXES_ENABLED_PREF_NAME "layout.css.prefixes.webkit"
 #define TEXT_ALIGN_UNSAFE_ENABLED_PREF_NAME "layout.css.text-align-unsafe-value.enabled"
 #define FLOAT_LOGICAL_VALUES_ENABLED_PREF_NAME "layout.css.float-logical-values.enabled"
@@ -214,51 +213,6 @@ static ContentMap& GetContentMap() {
   return *sContentMap;
 }
 
-// When the pref "layout.css.grid.enabled" changes, this function is invoked
-// to let us update kDisplayKTable, to selectively disable or restore the
-// entries for "grid" and "inline-grid" in that table.
-static void
-GridEnabledPrefChangeCallback(const char* aPrefName, void* aClosure)
-{
-  MOZ_ASSERT(strncmp(aPrefName, GRID_ENABLED_PREF_NAME,
-                     ArrayLength(GRID_ENABLED_PREF_NAME)) == 0,
-             "We only registered this callback for a single pref, so it "
-             "should only be called for that pref");
-
-  static int32_t sIndexOfGridInDisplayTable;
-  static int32_t sIndexOfInlineGridInDisplayTable;
-  static bool sAreGridKeywordIndicesInitialized; // initialized to false
-
-  bool isGridEnabled =
-    Preferences::GetBool(GRID_ENABLED_PREF_NAME, false);
-  if (!sAreGridKeywordIndicesInitialized) {
-    // First run: find the position of "grid" and "inline-grid" in
-    // kDisplayKTable.
-    sIndexOfGridInDisplayTable =
-      nsCSSProps::FindIndexOfKeyword(eCSSKeyword_grid,
-                                     nsCSSProps::kDisplayKTable);
-    MOZ_ASSERT(sIndexOfGridInDisplayTable >= 0,
-               "Couldn't find grid in kDisplayKTable");
-    sIndexOfInlineGridInDisplayTable =
-      nsCSSProps::FindIndexOfKeyword(eCSSKeyword_inline_grid,
-                                     nsCSSProps::kDisplayKTable);
-    MOZ_ASSERT(sIndexOfInlineGridInDisplayTable >= 0,
-               "Couldn't find inline-grid in kDisplayKTable");
-    sAreGridKeywordIndicesInitialized = true;
-  }
-
-  // OK -- now, stomp on or restore the "grid" entries in kDisplayKTable,
-  // depending on whether the grid pref is enabled vs. disabled.
-  if (sIndexOfGridInDisplayTable >= 0) {
-    nsCSSProps::kDisplayKTable[sIndexOfGridInDisplayTable].mKeyword =
-      isGridEnabled ? eCSSKeyword_grid : eCSSKeyword_UNKNOWN;
-  }
-  if (sIndexOfInlineGridInDisplayTable >= 0) {
-    nsCSSProps::kDisplayKTable[sIndexOfInlineGridInDisplayTable].mKeyword =
-      isGridEnabled ? eCSSKeyword_inline_grid : eCSSKeyword_UNKNOWN;
-  }
-}
-
 // When the pref "layout.css.prefixes.webkit" changes, this function is invoked
 // to let us update kDisplayKTable, to selectively disable or restore the
 // entries for "-webkit-box" and "-webkit-inline-box" in that table.
@@ -8159,8 +8113,6 @@ struct PrefCallbacks
   PrefChangedFunc func;
 };
 static const PrefCallbacks kPrefCallbacks[] = {
-  { GRID_ENABLED_PREF_NAME,
-    GridEnabledPrefChangeCallback },
   { WEBKIT_PREFIXES_ENABLED_PREF_NAME,
     WebkitPrefixEnabledPrefChangeCallback },
   { TEXT_ALIGN_UNSAFE_ENABLED_PREF_NAME,
diff --git a/layout/generic/crashtests/1015562.html b/layout/generic/crashtests/1015562.html
index 8975e64f2a6e..69fddcc7b281 100644
--- a/layout/generic/crashtests/1015562.html
+++ b/layout/generic/crashtests/1015562.html
@@ -2,11 +2,6 @@
 <html>
 <head>
 <script>
-
-/*
-user_pref("layout.css.grid.enabled", true);
-*/
-
 function boom()
 {
     document.getElementById("r").appendChild(document.createTextNode("B"));
diff --git a/layout/generic/crashtests/1156257.html b/layout/generic/crashtests/1156257.html
index e58c1ba5db89..47999262991f 100644
--- a/layout/generic/crashtests/1156257.html
+++ b/layout/generic/crashtests/1156257.html
@@ -2,9 +2,6 @@
 <html>
 <head>
 <meta charset="UTF-8">
-<!--
-user_pref("layout.css.grid.enabled", true);
--->
 <script>
 function boom()
 {
diff --git a/layout/generic/crashtests/crashtests.list b/layout/generic/crashtests/crashtests.list
index 1c87d280ce99..9c63f9266f09 100644
--- a/layout/generic/crashtests/crashtests.list
+++ b/layout/generic/crashtests/crashtests.list
@@ -574,7 +574,7 @@ load 1001233.html
 load 1001258-1.html
 load 1001994.html
 load 1003441.xul
-pref(layout.css.grid.enabled,true) load 1015562.html
+load 1015562.html
 asserts(1-2) load 1015563-1.html
 asserts(1-2) load 1015563-2.html
 asserts(11) asserts-if(stylo&&Android,274) load 1015844.html # bug 574889, bug 1374479
@@ -600,7 +600,7 @@ load 1146114.html
 asserts(0-20) load 1153478.html # bug 1144852
 load 1153695.html
 load 1156222.html
-pref(layout.css.grid.enabled,true) load 1156257.html
+load 1156257.html
 load 1157011.html
 load 1169420-1.html
 load 1169420-2.html
@@ -613,9 +613,9 @@ load 1223522.xhtml
 load 1223568-1.html
 load 1223568-2.html
 load 1224230-1.html
-pref(layout.css.grid.enabled,true) load 1225118.html
-pref(layout.css.grid.enabled,true) load 1225376.html
-pref(layout.css.grid.enabled,true) load 1225592.html
+load 1225118.html
+load 1225376.html
+load 1225592.html
 load 1229437-1.html
 load 1229437-2.html
 load details-containing-only-text.html
diff --git a/layout/reftests/bugs/reftest.list b/layout/reftests/bugs/reftest.list
index 92e5fa403f18..dd94c4f50f1a 100644
--- a/layout/reftests/bugs/reftest.list
+++ b/layout/reftests/bugs/reftest.list
@@ -1851,7 +1851,7 @@ pref(layout.css.moz-document.content.enabled,false) == 1035091-2.html 1035091-re
 == 1050493-1.html 1050493-1-ref.html
 == 1050788-1.html about:blank
 == 1053035-1-flex.html 1053035-1-ref.html
-test-pref(layout.css.grid.enabled,true) == 1053035-1-grid.html 1053035-1-ref.html
+== 1053035-1-grid.html 1053035-1-ref.html
 == 1059167-1.html 1059167-1-ref.html
 == 1059498-1.html 1059498-1-ref.html
 == 1059498-2.html 1059498-1-ref.html
diff --git a/layout/reftests/css-grid/reftest.list b/layout/reftests/css-grid/reftest.list
index 16cc877eda68..ceae2db1d120 100644
--- a/layout/reftests/css-grid/reftest.list
+++ b/layout/reftests/css-grid/reftest.list
@@ -1,5 +1,3 @@
-default-preferences pref(layout.css.grid.enabled,true)
-
 fails == grid-whitespace-handling-1a.xhtml grid-whitespace-handling-1-ref.xhtml
 fails == grid-whitespace-handling-1b.xhtml grid-whitespace-handling-1-ref.xhtml
 == grid-whitespace-handling-2.xhtml  grid-whitespace-handling-2-ref.xhtml
diff --git a/layout/reftests/list-item/reftest.list b/layout/reftests/list-item/reftest.list
index 034c173927eb..32fa524a3a17 100644
--- a/layout/reftests/list-item/reftest.list
+++ b/layout/reftests/list-item/reftest.list
@@ -1,6 +1,6 @@
 fuzzy-if(OSX,55,4) == numbering-1.html numbering-1-ref.html
 == numbering-2.html numbering-2-ref.html
-pref(layout.css.grid.enabled,true) fuzzy-if(OSX,8,1) == numbering-3.html numbering-3-ref.html
+fuzzy-if(OSX,8,1) == numbering-3.html numbering-3-ref.html
 fuzzy-if(OSX,72,2) == numbering-4.html numbering-4-ref.html
 == numbering-5.html numbering-5-ref.html
 == ol-reversed-1a.html ol-reversed-1-ref.html
diff --git a/layout/style/nsCSSPropList.h b/layout/style/nsCSSPropList.h
index 0daecb810ed9..84c185008806 100644
--- a/layout/style/nsCSSPropList.h
+++ b/layout/style/nsCSSPropList.h
@@ -2145,21 +2145,20 @@ CSS_PROP_SHORTHAND(
     grid,
     Grid,
     CSS_PROPERTY_PARSE_FUNCTION,
-    "layout.css.grid.enabled")
+    "")
 CSS_PROP_SHORTHAND(
     grid-area,
     grid_area,
     GridArea,
     CSS_PROPERTY_PARSE_FUNCTION,
-    "layout.css.grid.enabled")
+    "")
 CSS_PROP_POSITION(
     grid-auto-columns,
     grid_auto_columns,
     GridAutoColumns,
     CSS_PROPERTY_PARSE_FUNCTION |
-        CSS_PROPERTY_STORES_CALC |
-        CSS_PROPERTY_ENABLED_IN_UA_SHEETS,
-    "layout.css.grid.enabled",
+        CSS_PROPERTY_STORES_CALC,
+    "",
     0,
     kGridTrackBreadthKTable,
     CSS_PROP_NO_OFFSET,
@@ -2168,9 +2167,8 @@ CSS_PROP_POSITION(
     grid-auto-flow,
     grid_auto_flow,
     GridAutoFlow,
-    CSS_PROPERTY_PARSE_FUNCTION |
-        CSS_PROPERTY_ENABLED_IN_UA_SHEETS,
-    "layout.css.grid.enabled",
+    CSS_PROPERTY_PARSE_FUNCTION,
+    "",
     0,
     kGridAutoFlowKTable,
     CSS_PROP_NO_OFFSET,
@@ -2180,9 +2178,8 @@ CSS_PROP_POSITION(
     grid_auto_rows,
     GridAutoRows,
     CSS_PROPERTY_PARSE_FUNCTION |
-        CSS_PROPERTY_STORES_CALC |
-        CSS_PROPERTY_ENABLED_IN_UA_SHEETS,
-    "layout.css.grid.enabled",
+        CSS_PROPERTY_STORES_CALC,
+    "",
     0,
     kGridTrackBreadthKTable,
     CSS_PROP_NO_OFFSET,
@@ -2192,13 +2189,13 @@ CSS_PROP_SHORTHAND(
     grid_column,
     GridColumn,
     CSS_PROPERTY_PARSE_FUNCTION,
-    "layout.css.grid.enabled")
+    "")
 CSS_PROP_POSITION(
     grid-column-end,
     grid_column_end,
     GridColumnEnd,
     CSS_PROPERTY_PARSE_FUNCTION,
-    "layout.css.grid.enabled",
+    "",
     0,
     nullptr,
     CSS_PROP_NO_OFFSET,
@@ -2208,9 +2205,8 @@ CSS_PROP_POSITION(
     grid_column_gap,
     GridColumnGap,
     CSS_PROPERTY_PARSE_VALUE |
-        CSS_PROPERTY_VALUE_NONNEGATIVE |
-        CSS_PROPERTY_ENABLED_IN_UA_SHEETS,
-    "layout.css.grid.enabled",
+        CSS_PROPERTY_VALUE_NONNEGATIVE,
+    "",
     VARIANT_HLP | VARIANT_CALC,
     nullptr,
     offsetof(nsStylePosition, mGridColumnGap),
@@ -2220,7 +2216,7 @@ CSS_PROP_POSITION(
     grid_column_start,
     GridColumnStart,
     CSS_PROPERTY_PARSE_FUNCTION,
-    "layout.css.grid.enabled",
+    "",
     0,
     nullptr,
     CSS_PROP_NO_OFFSET,
@@ -2230,19 +2226,19 @@ CSS_PROP_SHORTHAND(
     grid_gap,
     GridGap,
     CSS_PROPERTY_PARSE_FUNCTION,
-    "layout.css.grid.enabled")
+    "")
 CSS_PROP_SHORTHAND(
     grid-row,
     grid_row,
     GridRow,
     CSS_PROPERTY_PARSE_FUNCTION,
-    "layout.css.grid.enabled")
+    "")
 CSS_PROP_POSITION(
     grid-row-end,
     grid_row_end,
     GridRowEnd,
     CSS_PROPERTY_PARSE_FUNCTION,
-    "layout.css.grid.enabled",
+    "",
     0,
     nullptr,
     CSS_PROP_NO_OFFSET,
@@ -2252,9 +2248,8 @@ CSS_PROP_POSITION(
     grid_row_gap,
     GridRowGap,
     CSS_PROPERTY_PARSE_VALUE |
-        CSS_PROPERTY_VALUE_NONNEGATIVE |
-        CSS_PROPERTY_ENABLED_IN_UA_SHEETS,
-    "layout.css.grid.enabled",
+        CSS_PROPERTY_VALUE_NONNEGATIVE,
+    "",
     VARIANT_HLP | VARIANT_CALC,
     nullptr,
     offsetof(nsStylePosition, mGridRowGap),
@@ -2264,7 +2259,7 @@ CSS_PROP_POSITION(
     grid_row_start,
     GridRowStart,
     CSS_PROPERTY_PARSE_FUNCTION,
-    "layout.css.grid.enabled",
+    "",
     0,
     nullptr,
     CSS_PROP_NO_OFFSET,
@@ -2274,14 +2269,13 @@ CSS_PROP_SHORTHAND(
     grid_template,
     GridTemplate,
     CSS_PROPERTY_PARSE_FUNCTION,
-    "layout.css.grid.enabled")
+    "")
 CSS_PROP_POSITION(
     grid-template-areas,
     grid_template_areas,
     GridTemplateAreas,
-    CSS_PROPERTY_PARSE_FUNCTION |
-        CSS_PROPERTY_ENABLED_IN_UA_SHEETS,
-    "layout.css.grid.enabled",
+    CSS_PROPERTY_PARSE_FUNCTION,
+    "",
     0,
     nullptr,
     CSS_PROP_NO_OFFSET,
@@ -2292,9 +2286,8 @@ CSS_PROP_POSITION(
     GridTemplateColumns,
     CSS_PROPERTY_PARSE_FUNCTION |
         CSS_PROPERTY_STORES_CALC |
-        CSS_PROPERTY_GETCS_NEEDS_LAYOUT_FLUSH |
-        CSS_PROPERTY_ENABLED_IN_UA_SHEETS,
-    "layout.css.grid.enabled",
+        CSS_PROPERTY_GETCS_NEEDS_LAYOUT_FLUSH,
+    "",
     0,
     kGridTrackBreadthKTable,
     CSS_PROP_NO_OFFSET,
@@ -2305,9 +2298,8 @@ CSS_PROP_POSITION(
     GridTemplateRows,
     CSS_PROPERTY_PARSE_FUNCTION |
         CSS_PROPERTY_STORES_CALC |
-        CSS_PROPERTY_GETCS_NEEDS_LAYOUT_FLUSH |
-        CSS_PROPERTY_ENABLED_IN_UA_SHEETS,
-    "layout.css.grid.enabled",
+        CSS_PROPERTY_GETCS_NEEDS_LAYOUT_FLUSH,
+    "",
     0,
     kGridTrackBreadthKTable,
     CSS_PROP_NO_OFFSET,
diff --git a/layout/style/nsCSSProps.cpp b/layout/style/nsCSSProps.cpp
index 90b2eb97ece7..2f7b054e2aae 100644
--- a/layout/style/nsCSSProps.cpp
+++ b/layout/style/nsCSSProps.cpp
@@ -1301,7 +1301,6 @@ KTableEntry nsCSSProps::kDisplayKTable[] = {
   { eCSSKeyword_ruby_base_container, StyleDisplay::RubyBaseContainer },
   { eCSSKeyword_ruby_text,           StyleDisplay::RubyText },
   { eCSSKeyword_ruby_text_container, StyleDisplay::RubyTextContainer },
-  // The next two entries are controlled by the layout.css.grid.enabled pref.
   { eCSSKeyword_grid,                StyleDisplay::Grid },
   { eCSSKeyword_inline_grid,         StyleDisplay::InlineGrid },
   // The next 4 entries are controlled by the layout.css.prefixes.webkit pref.
diff --git a/layout/style/nsLayoutStylesheetCache.cpp b/layout/style/nsLayoutStylesheetCache.cpp
index 97bfbba9ea91..4424828f754e 100644
--- a/layout/style/nsLayoutStylesheetCache.cpp
+++ b/layout/style/nsLayoutStylesheetCache.cpp
@@ -407,8 +407,6 @@ nsLayoutStylesheetCache::For(StyleBackendType aType)
     // style sheets will be re-parsed.
     // Preferences::RegisterCallback(&DependentPrefChanged,
     //                               "layout.css.example-pref.enabled");
-    Preferences::RegisterCallback(&DependentPrefChanged,
-                                  "layout.css.grid.enabled");
   }
 
   return cache;
@@ -865,7 +863,7 @@ nsLayoutStylesheetCache::DependentPrefChanged(const char* aPref, void* aData)
   InvalidateSheet(gStyleCache_Gecko ? &gStyleCache_Gecko->sheet_ : nullptr, \
                   gStyleCache_Servo ? &gStyleCache_Servo->sheet_ : nullptr);
 
-  INVALIDATE(mUASheet);  // for layout.css.grid.enabled
+  // INVALIDATE(mUASheet);  // for layout.css.example-pref.enabled
 
 #undef INVALIDATE
 }
diff --git a/layout/style/test/property_database.js b/layout/style/test/property_database.js
index 07dc69d55966..56c483b604ea 100644
--- a/layout/style/test/property_database.js
+++ b/layout/style/test/property_database.js
@@ -6676,559 +6676,557 @@ if (IsCSSPropertyPrefEnabled("layout.css.filters.enabled")) {
   }
 }
 
-if (IsCSSPropertyPrefEnabled("layout.css.grid.enabled")) {
-  var isGridTemplateSubgridValueEnabled =
-    IsCSSPropertyPrefEnabled("layout.css.grid-template-subgrid-value.enabled");
+var isGridTemplateSubgridValueEnabled =
+  IsCSSPropertyPrefEnabled("layout.css.grid-template-subgrid-value.enabled");
 
-  gCSSProperties["display"].other_values.push("grid", "inline-grid");
-  gCSSProperties["grid-auto-flow"] = {
-    domProp: "gridAutoFlow",
-    inherited: false,
-    type: CSS_TYPE_LONGHAND,
-    initial_values: [ "row" ],
-    other_values: [
-      "column",
-      "column dense",
-      "row dense",
-      "dense column",
-      "dense row",
-      "dense",
-    ],
-    invalid_values: [
-      "",
-      "auto",
-      "none",
-      "10px",
-      "column row",
-      "dense row dense",
-    ]
-  };
-
-  gCSSProperties["grid-auto-columns"] = {
-    domProp: "gridAutoColumns",
-    inherited: false,
-    type: CSS_TYPE_LONGHAND,
-    initial_values: [ "auto" ],
-    other_values: [
-      "40px",
-      "2em",
-      "2.5fr",
-      "12%",
-      "min-content",
-      "max-content",
-      "calc(2px - 99%)",
-      "minmax(20px, max-content)",
-      "minmax(min-content, auto)",
-      "minmax(auto, max-content)",
-      "m\\69nmax(20px, 4Fr)",
-      "MinMax(min-content, calc(20px + 10%))",
-      "fit-content(1px)",
-      "fit-content(calc(1px - 99%))",
-      "fit-content(10%)",
-    ],
-    invalid_values: [
-      "",
-      "normal",
-      "40ms",
-      "-40px",
-      "-12%",
-      "-2em",
-      "-2.5fr",
-      "minmax()",
-      "minmax(20px)",
-      "mİnmax(20px, 100px)",
-      "minmax(20px, 100px, 200px)",
-      "maxmin(100px, 20px)",
-      "minmax(min-content, minmax(30px, max-content))",
-      "fit-content(-1px)",
-      "fit-content(auto)",
-      "fit-content(min-content)",
-    ]
-  };
-  gCSSProperties["grid-auto-rows"] = {
-    domProp: "gridAutoRows",
-    inherited: false,
-    type: CSS_TYPE_LONGHAND,
-    initial_values: gCSSProperties["grid-auto-columns"].initial_values,
-    other_values: gCSSProperties["grid-auto-columns"].other_values,
-    invalid_values: gCSSProperties["grid-auto-columns"].invalid_values
-  };
-
-  gCSSProperties["grid-template-columns"] = {
-    domProp: "gridTemplateColumns",
-    inherited: false,
-    type: CSS_TYPE_LONGHAND,
-    initial_values: [ "none" ],
-    other_values: [
-      "auto",
-      "40px",
-      "2.5fr",
-      "[normal] 40px [] auto [ ] 12%",
-      "[foo] 40px min-content [ bar ] calc(2px - 99%) max-content",
-      "40px min-content calc(20px + 10%) max-content",
-      "minmax(min-content, auto)",
-      "minmax(auto, max-content)",
-      "m\\69nmax(20px, 4Fr)",
-      "40px MinMax(min-content, calc(20px + 10%)) max-content",
-      "40px 2em",
-      "[] 40px [-foo] 2em [bar baz This\ is\ one\ ident]",
-      // TODO bug 978478: "[a] repeat(3, [b] 20px [c] 40px [d]) [e]",
-      "repeat(1, 20px)",
-      "repeat(1, [a] 20px)",
-      "[a] Repeat(4, [a] 20px [] auto [b c]) [d]",
-      "[a] 2.5fr Repeat(4, [a] 20px [] auto [b c]) [d]",
-      "[a] 2.5fr [z] Repeat(4, [a] 20px [] auto [b c]) [d]",
-      "[a] 2.5fr [z] Repeat(4, [a] 20px [] auto) [d]",
-      "[a] 2.5fr [z] Repeat(4, 20px [b c] auto [b c]) [d]",
-      "[a] 2.5fr [z] Repeat(4, 20px auto) [d]",
-      "repeat(auto-fill, 0)",
-      "[a] repeat( Auto-fill,1%)",
-      "minmax(auto,0) [a] repeat(Auto-fit, 0) minmax(0,auto)",
-      "minmax(calc(1% + 1px),auto) repeat(Auto-fit,[] 1%) minmax(auto,1%)",
-      "[a] repeat( auto-fit,[a b] minmax(0,0) )",
-      "[a] 40px repeat(auto-fit,[a b] minmax(1px, 0) [])",
-      "[a] calc(1px - 99%) [b] repeat(auto-fit,[a b] minmax(1mm, 1%) [c]) [c]",
-      "repeat(auto-fill,minmax(1%,auto))",
-      "repeat(auto-fill,minmax(1em,min-content)) minmax(min-content,0)",
-      "repeat(auto-fill,minmax(max-content,1mm))",
-      "repeat(2, fit-content(1px))",
-      "fit-content(1px) 1fr",
-      "[a] fit-content(calc(1px - 99%)) [b]",
-      "[a] fit-content(10%) [b c] fit-content(1em)",
-    ],
-    invalid_values: [
-      "",
-      "normal",
-      "40ms",
-      "-40px",
-      "-12%",
-      "-2fr",
-      "[foo]",
-      "[inherit] 40px",
-      "[initial] 40px",
-      "[unset] 40px",
-      "[default] 40px",
-      "[span] 40px",
-      "[6%] 40px",
-      "[5th] 40px",
-      "[foo[] bar] 40px",
-      "[foo]] 40px",
-      "(foo) 40px",
-      "[foo] [bar] 40px",
-      "40px [foo] [bar]",
-      "minmax()",
-      "minmax(20px)",
-      "mİnmax(20px, 100px)",
-      "minmax(20px, 100px, 200px)",
-      "maxmin(100px, 20px)",
-      "minmax(min-content, minmax(30px, max-content))",
-      "repeat(0, 20px)",
-      "repeat(-3, 20px)",
-      "rêpeat(1, 20px)",
-      "repeat(1)",
-      "repeat(1, )",
-      "repeat(3px, 20px)",
-      "repeat(2.0, 20px)",
-      "repeat(2.5, 20px)",
-      "repeat(2, (foo))",
-      "repeat(2, foo)",
-      "40px calc(0px + rubbish)",
-      "repeat(1, repeat(1, 20px))",
-      "repeat(auto-fill, auto)",
-      "repeat(auto-fit,auto)",
-      "repeat(auto-fill, fit-content(1px))",
-      "repeat(auto-fit, fit-content(1px))",
-      "repeat(auto-fit,[])",
-      "repeat(auto-fill, 0) repeat(auto-fit, 0) ",
-      "repeat(auto-fit, 0) repeat(auto-fill, 0) ",
-      "[a] repeat(auto-fit, 0) repeat(auto-fit, 0) ",
-      "[a] repeat(auto-fill, 0) [a] repeat(auto-fill, 0) ",
-      "repeat(auto-fill, 0 0)",
-      "repeat(auto-fill, 0 [] 0)",
-      "repeat(auto-fill, min-content)",
-      "repeat(auto-fit,max-content)",
-      "repeat(auto-fit,1fr)",
-      "repeat(auto-fit,minmax(auto,auto))",
-      "repeat(auto-fit,minmax(min-content,1fr))",
-      "repeat(auto-fit,minmax(1fr,auto))",
-      "repeat(auto-fill,minmax(1fr,1em))",
-      "repeat(auto-fill, 10px) auto",
-      "auto repeat(auto-fit, 10px)",
-      "minmax(min-content,max-content) repeat(auto-fit, 0)",
-      "10px [a] 10px [b a] 1fr [b] repeat(auto-fill, 0)",
-      "fit-content(-1px)",
-      "fit-content(auto)",
-      "fit-content(min-content)",
-      "fit-content(1px) repeat(auto-fit, 1px)",
-      "fit-content(1px) repeat(auto-fill, 1px)",
-    ],
-    unbalanced_values: [
-      "(foo] 40px",
-    ]
-  };
-  if (isGridTemplateSubgridValueEnabled) {
-    gCSSProperties["grid-template-columns"].other_values.push(
-      // See https://bugzilla.mozilla.org/show_bug.cgi?id=981300
-      "[none auto subgrid min-content max-content foo] 40px",
-
-      "subgrid",
-      "subgrid [] [foo bar]",
-      "subgrid repeat(1, [])",
-      "subgrid Repeat(4, [a] [b c] [] [d])",
-      "subgrid repeat(auto-fill, [])",
-      "subgrid [x] repeat( Auto-fill, [a b c]) []",
-      "subgrid [x] repeat(auto-fill, []) [y z]"
-    );
-    gCSSProperties["grid-template-columns"].invalid_values.push(
-      "subgrid [inherit]",
-      "subgrid [initial]",
-      "subgrid [unset]",
-      "subgrid [default]",
-      "subgrid [span]",
-      "subgrid [foo] 40px",
-      "subgrid [foo 40px]",
-      "[foo] subgrid",
-      "subgrid rêpeat(1, [])",
-      "subgrid repeat(0, [])",
-      "subgrid repeat(-3, [])",
-      "subgrid repeat(2.0, [])",
-      "subgrid repeat(2.5, [])",
-      "subgrid repeat(3px, [])",
-      "subgrid repeat(1)",
-      "subgrid repeat(1, )",
-      "subgrid repeat(2, [40px])",
-      "subgrid repeat(2, foo)",
-      "subgrid repeat(1, repeat(1, []))",
-      "subgrid repeat(auto-fit,[])",
-      "subgrid [] repeat(auto-fit,[])",
-      "subgrid [a] repeat(auto-fit,[])",
-      "subgrid repeat(auto-fill, 1px)",
-      "subgrid repeat(auto-fill, 1px [])",
-      "subgrid repeat(Auto-fill, [a] [b c] [] [d])",
-      "subgrid repeat(auto-fill, []) repeat(auto-fill, [])"
-    );
-  }
-  gCSSProperties["grid-template-rows"] = {
-    domProp: "gridTemplateRows",
-    inherited: false,
-    type: CSS_TYPE_LONGHAND,
-    initial_values: gCSSProperties["grid-template-columns"].initial_values,
-    other_values: gCSSProperties["grid-template-columns"].other_values,
-    invalid_values: gCSSProperties["grid-template-columns"].invalid_values
-  };
-  gCSSProperties["grid-template-areas"] = {
-    domProp: "gridTemplateAreas",
-    inherited: false,
-    type: CSS_TYPE_LONGHAND,
-    initial_values: [ "none" ],
-    other_values: [
-      "''",
-      "'' ''",
-      "'1a-é_ .' \"b .\"",
-      "' Z\t\\aZ' 'Z Z'",
-      " '. . a b'  '. .a b' ",
-      "'a.b' '. . .'",
-      "'.' '..'",
-      "'...' '.'",
-      "'...-blah' '. .'",
-      "'.. ..' '.. ...'",
-    ],
-    invalid_values: [
-      "'a b' 'a/b'",
-      "'a . a'",
-      "'. a a' 'a a a'",
-      "'a a .' 'a a a'",
-      "'a a' 'a .'",
-      "'a a'\n'..'\n'a a'",
-    ]
-  };
-
-  gCSSProperties["grid-template"] = {
-    domProp: "gridTemplate",
-    inherited: false,
-    type: CSS_TYPE_TRUE_SHORTHAND,
-    subproperties: [
-      "grid-template-areas",
-      "grid-template-rows",
-      "grid-template-columns",
-    ],
-    initial_values: [
-      "none",
-      "none / none",
-    ],
-    other_values: [
-      // <'grid-template-rows'> / <'grid-template-columns'>
-      "40px / 100px",
-      "[foo] 40px [bar] / [baz] repeat(auto-fill,100px) [fizz]",
-      " none/100px",
-      "40px/none",
-      // [ <line-names>? <string> <track-size>? <line-names>? ]+ [ / <explicit-track-list> ]?
-      "'fizz'",
-      "[bar] 'fizz'",
-      "'fizz' / [foo] 40px",
-      "[bar] 'fizz' / [foo] 40px",
-      "'fizz' 100px / [foo] 40px",
-      "[bar] 'fizz' 100px / [foo] 40px",
-      "[bar] 'fizz' 100px [buzz] / [foo] 40px",
-      "[bar] 'fizz' 100px [buzz] \n [a] '.' 200px [b] / [foo] 40px",
-    ],
-    invalid_values: [
-      "'fizz' / repeat(1, 100px)",
-      "'fizz' repeat(1, 100px) / 0px",
-      "[foo] [bar] 40px / 100px",
-      "[fizz] [buzz] 100px / 40px",
-      "[fizz] [buzz] 'foo' / 40px",
-      "'foo' / none"
-    ]
-  };
-  if (isGridTemplateSubgridValueEnabled) {
-    gCSSProperties["grid-template"].other_values.push(
-      "subgrid",
-      "subgrid/40px 20px",
-      "subgrid [foo] [] [bar baz] / 40px 20px",
-      "40px 20px/subgrid",
-      "40px 20px/subgrid  [foo] [] repeat(3, [a] [b]) [bar baz]",
-      "subgrid/subgrid",
-      "subgrid [foo] [] [bar baz]/subgrid [foo] [] [bar baz]"
-    );
-    gCSSProperties["grid-template"].invalid_values.push(
-      "subgrid []",
-      "subgrid [] / 'fizz'",
-      "subgrid / 'fizz'"
-    );
-  }
-
-  gCSSProperties["grid"] = {
-    domProp: "grid",
-    inherited: false,
-    type: CSS_TYPE_TRUE_SHORTHAND,
-    subproperties: [
-      "grid-template-areas",
-      "grid-template-rows",
-      "grid-template-columns",
-      "grid-auto-flow",
-      "grid-auto-rows",
-      "grid-auto-columns",
-    ],
-    initial_values: [
-      "none",
-      "none / none",
-    ],
-    other_values: [
-      "auto-flow 40px / none",
-      "auto-flow / 40px",
-      "auto-flow dense auto / auto",
-      "dense auto-flow minmax(min-content, 2fr) / auto",
-      "dense auto-flow / 100px",
-      "none / auto-flow 40px",
-      "40px / auto-flow",
-      "none / dense auto-flow auto",
-    ].concat(
-      gCSSProperties["grid-template"].other_values
-    ),
-    invalid_values: [
-      "auto-flow",
-      " / auto-flow",
-      "dense 0 / 0",
-      "dense dense 40px / 0",
-      "auto-flow / auto-flow",
-      "auto-flow / dense",
-      "auto-flow [a] 0 / 0",
-      "0 / auto-flow [a] 0",
-      "auto-flow -20px / 0",
-      "auto-flow 200ms / 0",
-      "auto-flow 40px 100px / 0",
-    ].concat(
-      gCSSProperties["grid-template"].invalid_values,
-      gCSSProperties["grid-auto-flow"].other_values,
-      gCSSProperties["grid-auto-flow"].invalid_values
-        .filter((v) => v != 'none')
-    )
-  };
-
-  var gridLineOtherValues = [
-    "foo",
-    "2",
-    "2 foo",
-    "foo 2",
-    "-3",
-    "-3 bar",
-    "bar -3",
-    "span 2",
-    "2 span",
-    "span foo",
-    "foo span",
-    "span 2 foo",
-    "span foo 2",
-    "2 foo span",
-    "foo 2 span",
-  ];
-  var gridLineInvalidValues = [
+gCSSProperties["display"].other_values.push("grid", "inline-grid");
+gCSSProperties["grid-auto-flow"] = {
+  domProp: "gridAutoFlow",
+  inherited: false,
+  type: CSS_TYPE_LONGHAND,
+  initial_values: [ "row" ],
+  other_values: [
+    "column",
+    "column dense",
+    "row dense",
+    "dense column",
+    "dense row",
+    "dense",
+  ],
+  invalid_values: [
     "",
-    "4th",
-    "span",
-    "inherit 2",
-    "2 inherit",
-    "20px",
-    "2 3",
-    "2.5",
-    "2.0",
-    "0",
-    "0 foo",
-    "span 0",
-    "2 foo 3",
-    "foo 2 foo",
-    "2 span foo",
-    "foo span 2",
-    "span -3",
-    "span -3 bar",
-    "span 2 span",
-    "span foo span",
-    "span 2 foo span",
-  ];
+    "auto",
+    "none",
+    "10px",
+    "column row",
+    "dense row dense",
+  ]
+};
 
-  gCSSProperties["grid-column-start"] = {
-    domProp: "gridColumnStart",
-    inherited: false,
-    type: CSS_TYPE_LONGHAND,
-    initial_values: [ "auto" ],
-    other_values: gridLineOtherValues,
-    invalid_values: gridLineInvalidValues
-  };
-  gCSSProperties["grid-column-end"] = {
-    domProp: "gridColumnEnd",
-    inherited: false,
-    type: CSS_TYPE_LONGHAND,
-    initial_values: [ "auto" ],
-    other_values: gridLineOtherValues,
-    invalid_values: gridLineInvalidValues
-  };
-  gCSSProperties["grid-row-start"] = {
-    domProp: "gridRowStart",
-    inherited: false,
-    type: CSS_TYPE_LONGHAND,
-    initial_values: [ "auto" ],
-    other_values: gridLineOtherValues,
-    invalid_values: gridLineInvalidValues
-  };
-  gCSSProperties["grid-row-end"] = {
-    domProp: "gridRowEnd",
-    inherited: false,
-    type: CSS_TYPE_LONGHAND,
-    initial_values: [ "auto" ],
-    other_values: gridLineOtherValues,
-    invalid_values: gridLineInvalidValues
-  };
+gCSSProperties["grid-auto-columns"] = {
+  domProp: "gridAutoColumns",
+  inherited: false,
+  type: CSS_TYPE_LONGHAND,
+  initial_values: [ "auto" ],
+  other_values: [
+    "40px",
+    "2em",
+    "2.5fr",
+    "12%",
+    "min-content",
+    "max-content",
+    "calc(2px - 99%)",
+    "minmax(20px, max-content)",
+    "minmax(min-content, auto)",
+    "minmax(auto, max-content)",
+    "m\\69nmax(20px, 4Fr)",
+    "MinMax(min-content, calc(20px + 10%))",
+    "fit-content(1px)",
+    "fit-content(calc(1px - 99%))",
+    "fit-content(10%)",
+  ],
+  invalid_values: [
+    "",
+    "normal",
+    "40ms",
+    "-40px",
+    "-12%",
+    "-2em",
+    "-2.5fr",
+    "minmax()",
+    "minmax(20px)",
+    "mİnmax(20px, 100px)",
+    "minmax(20px, 100px, 200px)",
+    "maxmin(100px, 20px)",
+    "minmax(min-content, minmax(30px, max-content))",
+    "fit-content(-1px)",
+    "fit-content(auto)",
+    "fit-content(min-content)",
+  ]
+};
+gCSSProperties["grid-auto-rows"] = {
+  domProp: "gridAutoRows",
+  inherited: false,
+  type: CSS_TYPE_LONGHAND,
+  initial_values: gCSSProperties["grid-auto-columns"].initial_values,
+  other_values: gCSSProperties["grid-auto-columns"].other_values,
+  invalid_values: gCSSProperties["grid-auto-columns"].invalid_values
+};
 
-  // The grid-column and grid-row shorthands take values of the form
-  //   <grid-line> [ / <grid-line> ]?
-  var gridColumnRowOtherValues = [].concat(gridLineOtherValues);
-  gridLineOtherValues.concat([ "auto" ]).forEach(function(val) {
-    gridColumnRowOtherValues.push(" foo / " + val);
-    gridColumnRowOtherValues.push(val + "/2");
-  });
-  var gridColumnRowInvalidValues = [
-    "foo, bar",
-    "foo / bar / baz",
-  ].concat(gridLineInvalidValues);
-  gridLineInvalidValues.forEach(function(val) {
-    gridColumnRowInvalidValues.push("span 3 / " + val);
-    gridColumnRowInvalidValues.push(val + " / foo");
-  });
-  gCSSProperties["grid-column"] = {
-    domProp: "gridColumn",
-    inherited: false,
-    type: CSS_TYPE_TRUE_SHORTHAND,
-    subproperties: [
-      "grid-column-start",
-      "grid-column-end"
-    ],
-    initial_values: [ "auto", "auto / auto" ],
-    other_values: gridColumnRowOtherValues,
-    invalid_values: gridColumnRowInvalidValues
-  };
-  gCSSProperties["grid-row"] = {
-    domProp: "gridRow",
-    inherited: false,
-    type: CSS_TYPE_TRUE_SHORTHAND,
-    subproperties: [
-      "grid-row-start",
-      "grid-row-end"
-    ],
-    initial_values: [ "auto", "auto / auto" ],
-    other_values: gridColumnRowOtherValues,
-    invalid_values: gridColumnRowInvalidValues
-  };
+gCSSProperties["grid-template-columns"] = {
+  domProp: "gridTemplateColumns",
+  inherited: false,
+  type: CSS_TYPE_LONGHAND,
+  initial_values: [ "none" ],
+  other_values: [
+    "auto",
+    "40px",
+    "2.5fr",
+    "[normal] 40px [] auto [ ] 12%",
+    "[foo] 40px min-content [ bar ] calc(2px - 99%) max-content",
+    "40px min-content calc(20px + 10%) max-content",
+    "minmax(min-content, auto)",
+    "minmax(auto, max-content)",
+    "m\\69nmax(20px, 4Fr)",
+    "40px MinMax(min-content, calc(20px + 10%)) max-content",
+    "40px 2em",
+    "[] 40px [-foo] 2em [bar baz This\ is\ one\ ident]",
+    // TODO bug 978478: "[a] repeat(3, [b] 20px [c] 40px [d]) [e]",
+    "repeat(1, 20px)",
+    "repeat(1, [a] 20px)",
+    "[a] Repeat(4, [a] 20px [] auto [b c]) [d]",
+    "[a] 2.5fr Repeat(4, [a] 20px [] auto [b c]) [d]",
+    "[a] 2.5fr [z] Repeat(4, [a] 20px [] auto [b c]) [d]",
+    "[a] 2.5fr [z] Repeat(4, [a] 20px [] auto) [d]",
+    "[a] 2.5fr [z] Repeat(4, 20px [b c] auto [b c]) [d]",
+    "[a] 2.5fr [z] Repeat(4, 20px auto) [d]",
+    "repeat(auto-fill, 0)",
+    "[a] repeat( Auto-fill,1%)",
+    "minmax(auto,0) [a] repeat(Auto-fit, 0) minmax(0,auto)",
+    "minmax(calc(1% + 1px),auto) repeat(Auto-fit,[] 1%) minmax(auto,1%)",
+    "[a] repeat( auto-fit,[a b] minmax(0,0) )",
+    "[a] 40px repeat(auto-fit,[a b] minmax(1px, 0) [])",
+    "[a] calc(1px - 99%) [b] repeat(auto-fit,[a b] minmax(1mm, 1%) [c]) [c]",
+    "repeat(auto-fill,minmax(1%,auto))",
+    "repeat(auto-fill,minmax(1em,min-content)) minmax(min-content,0)",
+    "repeat(auto-fill,minmax(max-content,1mm))",
+    "repeat(2, fit-content(1px))",
+    "fit-content(1px) 1fr",
+    "[a] fit-content(calc(1px - 99%)) [b]",
+    "[a] fit-content(10%) [b c] fit-content(1em)",
+  ],
+  invalid_values: [
+    "",
+    "normal",
+    "40ms",
+    "-40px",
+    "-12%",
+    "-2fr",
+    "[foo]",
+    "[inherit] 40px",
+    "[initial] 40px",
+    "[unset] 40px",
+    "[default] 40px",
+    "[span] 40px",
+    "[6%] 40px",
+    "[5th] 40px",
+    "[foo[] bar] 40px",
+    "[foo]] 40px",
+    "(foo) 40px",
+    "[foo] [bar] 40px",
+    "40px [foo] [bar]",
+    "minmax()",
+    "minmax(20px)",
+    "mİnmax(20px, 100px)",
+    "minmax(20px, 100px, 200px)",
+    "maxmin(100px, 20px)",
+    "minmax(min-content, minmax(30px, max-content))",
+    "repeat(0, 20px)",
+    "repeat(-3, 20px)",
+    "rêpeat(1, 20px)",
+    "repeat(1)",
+    "repeat(1, )",
+    "repeat(3px, 20px)",
+    "repeat(2.0, 20px)",
+    "repeat(2.5, 20px)",
+    "repeat(2, (foo))",
+    "repeat(2, foo)",
+    "40px calc(0px + rubbish)",
+    "repeat(1, repeat(1, 20px))",
+    "repeat(auto-fill, auto)",
+    "repeat(auto-fit,auto)",
+    "repeat(auto-fill, fit-content(1px))",
+    "repeat(auto-fit, fit-content(1px))",
+    "repeat(auto-fit,[])",
+    "repeat(auto-fill, 0) repeat(auto-fit, 0) ",
+    "repeat(auto-fit, 0) repeat(auto-fill, 0) ",
+    "[a] repeat(auto-fit, 0) repeat(auto-fit, 0) ",
+    "[a] repeat(auto-fill, 0) [a] repeat(auto-fill, 0) ",
+    "repeat(auto-fill, 0 0)",
+    "repeat(auto-fill, 0 [] 0)",
+    "repeat(auto-fill, min-content)",
+    "repeat(auto-fit,max-content)",
+    "repeat(auto-fit,1fr)",
+    "repeat(auto-fit,minmax(auto,auto))",
+    "repeat(auto-fit,minmax(min-content,1fr))",
+    "repeat(auto-fit,minmax(1fr,auto))",
+    "repeat(auto-fill,minmax(1fr,1em))",
+    "repeat(auto-fill, 10px) auto",
+    "auto repeat(auto-fit, 10px)",
+    "minmax(min-content,max-content) repeat(auto-fit, 0)",
+    "10px [a] 10px [b a] 1fr [b] repeat(auto-fill, 0)",
+    "fit-content(-1px)",
+    "fit-content(auto)",
+    "fit-content(min-content)",
+    "fit-content(1px) repeat(auto-fit, 1px)",
+    "fit-content(1px) repeat(auto-fill, 1px)",
+  ],
+  unbalanced_values: [
+    "(foo] 40px",
+  ]
+};
+if (isGridTemplateSubgridValueEnabled) {
+  gCSSProperties["grid-template-columns"].other_values.push(
+    // See https://bugzilla.mozilla.org/show_bug.cgi?id=981300
+    "[none auto subgrid min-content max-content foo] 40px",
 
-  var gridAreaOtherValues = gridLineOtherValues.slice();
-  gridLineOtherValues.forEach(function(val) {
-    gridAreaOtherValues.push("foo / " + val);
-    gridAreaOtherValues.push(val + "/2/3");
-    gridAreaOtherValues.push("foo / bar / " + val + " / baz");
-  });
-  var gridAreaInvalidValues = [
-    "foo, bar",
-    "foo / bar / baz / fizz / buzz",
-    "default / foo / bar / baz",
-    "foo / initial / bar / baz",
-    "foo / bar / inherit / baz",
-    "foo / bar / baz / unset",
-  ].concat(gridLineInvalidValues);
-  gridLineInvalidValues.forEach(function(val) {
-    gridAreaInvalidValues.push("foo / " + val);
-    gridAreaInvalidValues.push("foo / bar / " + val);
-    gridAreaInvalidValues.push("foo / 4 / bar / " + val);
-  });
-
-  gCSSProperties["grid-area"] = {
-    domProp: "gridArea",
-    inherited: false,
-    type: CSS_TYPE_TRUE_SHORTHAND,
-    subproperties: [
-      "grid-row-start",
-      "grid-column-start",
-      "grid-row-end",
-      "grid-column-end"
-    ],
-    initial_values: [
-      "auto",
-      "auto / auto",
-      "auto / auto / auto",
-      "auto / auto / auto / auto"
-    ],
-    other_values: gridAreaOtherValues,
-    invalid_values: gridAreaInvalidValues
-  };
-
-  gCSSProperties["grid-column-gap"] = {
-    domProp: "gridColumnGap",
-    inherited: false,
-    type: CSS_TYPE_LONGHAND,
-    initial_values: [ "0" ],
-    other_values: [ "2px", "2%", "1em", "calc(1px + 1em)", "calc(1%)",
-                    "calc(1% + 1ch)" , "calc(1px - 99%)" ],
-    invalid_values: [ "-1px", "auto", "none", "1px 1px", "-1%", "fit-content(1px)" ],
-  };
-  gCSSProperties["grid-row-gap"] = {
-    domProp: "gridRowGap",
-    inherited: false,
-    type: CSS_TYPE_LONGHAND,
-    initial_values: [ "0" ],
-    other_values: [ "2px", "2%", "1em", "calc(1px + 1em)", "calc(1%)",
-                    "calc(1% + 1ch)" , "calc(1px - 99%)" ],
-    invalid_values: [ "-1px", "auto", "none", "1px 1px", "-1%", "min-content" ],
-  };
-  gCSSProperties["grid-gap"] = {
-    domProp: "gridGap",
-    inherited: false,
-    type: CSS_TYPE_TRUE_SHORTHAND,
-    subproperties: [ "grid-column-gap", "grid-row-gap" ],
-    initial_values: [ "0", "0 0" ],
-    other_values: [ "1ch 0", "1px 1%", "1em 1px", "calc(1px) calc(1%)" ],
-    invalid_values: [ "-1px", "1px -1px", "1px 1px 1px", "inherit 1px",
-                      "1px auto" ]
-  };
+    "subgrid",
+    "subgrid [] [foo bar]",
+    "subgrid repeat(1, [])",
+    "subgrid Repeat(4, [a] [b c] [] [d])",
+    "subgrid repeat(auto-fill, [])",
+    "subgrid [x] repeat( Auto-fill, [a b c]) []",
+    "subgrid [x] repeat(auto-fill, []) [y z]"
+  );
+  gCSSProperties["grid-template-columns"].invalid_values.push(
+    "subgrid [inherit]",
+    "subgrid [initial]",
+    "subgrid [unset]",
+    "subgrid [default]",
+    "subgrid [span]",
+    "subgrid [foo] 40px",
+    "subgrid [foo 40px]",
+    "[foo] subgrid",
+    "subgrid rêpeat(1, [])",
+    "subgrid repeat(0, [])",
+    "subgrid repeat(-3, [])",
+    "subgrid repeat(2.0, [])",
+    "subgrid repeat(2.5, [])",
+    "subgrid repeat(3px, [])",
+    "subgrid repeat(1)",
+    "subgrid repeat(1, )",
+    "subgrid repeat(2, [40px])",
+    "subgrid repeat(2, foo)",
+    "subgrid repeat(1, repeat(1, []))",
+    "subgrid repeat(auto-fit,[])",
+    "subgrid [] repeat(auto-fit,[])",
+    "subgrid [a] repeat(auto-fit,[])",
+    "subgrid repeat(auto-fill, 1px)",
+    "subgrid repeat(auto-fill, 1px [])",
+    "subgrid repeat(Auto-fill, [a] [b c] [] [d])",
+    "subgrid repeat(auto-fill, []) repeat(auto-fill, [])"
+  );
 }
+gCSSProperties["grid-template-rows"] = {
+  domProp: "gridTemplateRows",
+  inherited: false,
+  type: CSS_TYPE_LONGHAND,
+  initial_values: gCSSProperties["grid-template-columns"].initial_values,
+  other_values: gCSSProperties["grid-template-columns"].other_values,
+  invalid_values: gCSSProperties["grid-template-columns"].invalid_values
+};
+gCSSProperties["grid-template-areas"] = {
+  domProp: "gridTemplateAreas",
+  inherited: false,
+  type: CSS_TYPE_LONGHAND,
+  initial_values: [ "none" ],
+  other_values: [
+    "''",
+    "'' ''",
+    "'1a-é_ .' \"b .\"",
+    "' Z\t\\aZ' 'Z Z'",
+    " '. . a b'  '. .a b' ",
+    "'a.b' '. . .'",
+    "'.' '..'",
+    "'...' '.'",
+    "'...-blah' '. .'",
+    "'.. ..' '.. ...'",
+  ],
+  invalid_values: [
+    "'a b' 'a/b'",
+    "'a . a'",
+    "'. a a' 'a a a'",
+    "'a a .' 'a a a'",
+    "'a a' 'a .'",
+    "'a a'\n'..'\n'a a'",
+  ]
+};
+
+gCSSProperties["grid-template"] = {
+  domProp: "gridTemplate",
+  inherited: false,
+  type: CSS_TYPE_TRUE_SHORTHAND,
+  subproperties: [
+    "grid-template-areas",
+    "grid-template-rows",
+    "grid-template-columns",
+  ],
+  initial_values: [
+    "none",
+    "none / none",
+  ],
+  other_values: [
+    // <'grid-template-rows'> / <'grid-template-columns'>
+    "40px / 100px",
+    "[foo] 40px [bar] / [baz] repeat(auto-fill,100px) [fizz]",
+    " none/100px",
+    "40px/none",
+    // [ <line-names>? <string> <track-size>? <line-names>? ]+ [ / <explicit-track-list> ]?
+    "'fizz'",
+    "[bar] 'fizz'",
+    "'fizz' / [foo] 40px",
+    "[bar] 'fizz' / [foo] 40px",
+    "'fizz' 100px / [foo] 40px",
+    "[bar] 'fizz' 100px / [foo] 40px",
+    "[bar] 'fizz' 100px [buzz] / [foo] 40px",
+    "[bar] 'fizz' 100px [buzz] \n [a] '.' 200px [b] / [foo] 40px",
+  ],
+  invalid_values: [
+    "'fizz' / repeat(1, 100px)",
+    "'fizz' repeat(1, 100px) / 0px",
+    "[foo] [bar] 40px / 100px",
+    "[fizz] [buzz] 100px / 40px",
+    "[fizz] [buzz] 'foo' / 40px",
+    "'foo' / none"
+  ]
+};
+if (isGridTemplateSubgridValueEnabled) {
+  gCSSProperties["grid-template"].other_values.push(
+    "subgrid",
+    "subgrid/40px 20px",
+    "subgrid [foo] [] [bar baz] / 40px 20px",
+    "40px 20px/subgrid",
+    "40px 20px/subgrid  [foo] [] repeat(3, [a] [b]) [bar baz]",
+    "subgrid/subgrid",
+    "subgrid [foo] [] [bar baz]/subgrid [foo] [] [bar baz]"
+  );
+  gCSSProperties["grid-template"].invalid_values.push(
+    "subgrid []",
+    "subgrid [] / 'fizz'",
+    "subgrid / 'fizz'"
+  );
+}
+
+gCSSProperties["grid"] = {
+  domProp: "grid",
+  inherited: false,
+  type: CSS_TYPE_TRUE_SHORTHAND,
+  subproperties: [
+    "grid-template-areas",
+    "grid-template-rows",
+    "grid-template-columns",
+    "grid-auto-flow",
+    "grid-auto-rows",
+    "grid-auto-columns",
+  ],
+  initial_values: [
+    "none",
+    "none / none",
+  ],
+  other_values: [
+    "auto-flow 40px / none",
+    "auto-flow / 40px",
+    "auto-flow dense auto / auto",
+    "dense auto-flow minmax(min-content, 2fr) / auto",
+    "dense auto-flow / 100px",
+    "none / auto-flow 40px",
+    "40px / auto-flow",
+    "none / dense auto-flow auto",
+  ].concat(
+    gCSSProperties["grid-template"].other_values
+  ),
+  invalid_values: [
+    "auto-flow",
+    " / auto-flow",
+    "dense 0 / 0",
+    "dense dense 40px / 0",
+    "auto-flow / auto-flow",
+    "auto-flow / dense",
+    "auto-flow [a] 0 / 0",
+    "0 / auto-flow [a] 0",
+    "auto-flow -20px / 0",
+    "auto-flow 200ms / 0",
+    "auto-flow 40px 100px / 0",
+  ].concat(
+    gCSSProperties["grid-template"].invalid_values,
+    gCSSProperties["grid-auto-flow"].other_values,
+    gCSSProperties["grid-auto-flow"].invalid_values
+      .filter((v) => v != 'none')
+  )
+};
+
+var gridLineOtherValues = [
+  "foo",
+  "2",
+  "2 foo",
+  "foo 2",
+  "-3",
+  "-3 bar",
+  "bar -3",
+  "span 2",
+  "2 span",
+  "span foo",
+  "foo span",
+  "span 2 foo",
+  "span foo 2",
+  "2 foo span",
+  "foo 2 span",
+];
+var gridLineInvalidValues = [
+  "",
+  "4th",
+  "span",
+  "inherit 2",
+  "2 inherit",
+  "20px",
+  "2 3",
+  "2.5",
+  "2.0",
+  "0",
+  "0 foo",
+  "span 0",
+  "2 foo 3",
+  "foo 2 foo",
+  "2 span foo",
+  "foo span 2",
+  "span -3",
+  "span -3 bar",
+  "span 2 span",
+  "span foo span",
+  "span 2 foo span",
+];
+
+gCSSProperties["grid-column-start"] = {
+  domProp: "gridColumnStart",
+  inherited: false,
+  type: CSS_TYPE_LONGHAND,
+  initial_values: [ "auto" ],
+  other_values: gridLineOtherValues,
+  invalid_values: gridLineInvalidValues
+};
+gCSSProperties["grid-column-end"] = {
+  domProp: "gridColumnEnd",
+  inherited: false,
+  type: CSS_TYPE_LONGHAND,
+  initial_values: [ "auto" ],
+  other_values: gridLineOtherValues,
+  invalid_values: gridLineInvalidValues
+};
+gCSSProperties["grid-row-start"] = {
+  domProp: "gridRowStart",
+  inherited: false,
+  type: CSS_TYPE_LONGHAND,
+  initial_values: [ "auto" ],
+  other_values: gridLineOtherValues,
+  invalid_values: gridLineInvalidValues
+};
+gCSSProperties["grid-row-end"] = {
+  domProp: "gridRowEnd",
+  inherited: false,
+  type: CSS_TYPE_LONGHAND,
+  initial_values: [ "auto" ],
+  other_values: gridLineOtherValues,
+  invalid_values: gridLineInvalidValues
+};
+
+// The grid-column and grid-row shorthands take values of the form
+//   <grid-line> [ / <grid-line> ]?
+var gridColumnRowOtherValues = [].concat(gridLineOtherValues);
+gridLineOtherValues.concat([ "auto" ]).forEach(function(val) {
+  gridColumnRowOtherValues.push(" foo / " + val);
+  gridColumnRowOtherValues.push(val + "/2");
+});
+var gridColumnRowInvalidValues = [
+  "foo, bar",
+  "foo / bar / baz",
+].concat(gridLineInvalidValues);
+gridLineInvalidValues.forEach(function(val) {
+  gridColumnRowInvalidValues.push("span 3 / " + val);
+  gridColumnRowInvalidValues.push(val + " / foo");
+});
+gCSSProperties["grid-column"] = {
+  domProp: "gridColumn",
+  inherited: false,
+  type: CSS_TYPE_TRUE_SHORTHAND,
+  subproperties: [
+    "grid-column-start",
+    "grid-column-end"
+  ],
+  initial_values: [ "auto", "auto / auto" ],
+  other_values: gridColumnRowOtherValues,
+  invalid_values: gridColumnRowInvalidValues
+};
+gCSSProperties["grid-row"] = {
+  domProp: "gridRow",
+  inherited: false,
+  type: CSS_TYPE_TRUE_SHORTHAND,
+  subproperties: [
+    "grid-row-start",
+    "grid-row-end"
+  ],
+  initial_values: [ "auto", "auto / auto" ],
+  other_values: gridColumnRowOtherValues,
+  invalid_values: gridColumnRowInvalidValues
+};
+
+var gridAreaOtherValues = gridLineOtherValues.slice();
+gridLineOtherValues.forEach(function(val) {
+  gridAreaOtherValues.push("foo / " + val);
+  gridAreaOtherValues.push(val + "/2/3");
+  gridAreaOtherValues.push("foo / bar / " + val + " / baz");
+});
+var gridAreaInvalidValues = [
+  "foo, bar",
+  "foo / bar / baz / fizz / buzz",
+  "default / foo / bar / baz",
+  "foo / initial / bar / baz",
+  "foo / bar / inherit / baz",
+  "foo / bar / baz / unset",
+].concat(gridLineInvalidValues);
+gridLineInvalidValues.forEach(function(val) {
+  gridAreaInvalidValues.push("foo / " + val);
+  gridAreaInvalidValues.push("foo / bar / " + val);
+  gridAreaInvalidValues.push("foo / 4 / bar / " + val);
+});
+
+gCSSProperties["grid-area"] = {
+  domProp: "gridArea",
+  inherited: false,
+  type: CSS_TYPE_TRUE_SHORTHAND,
+  subproperties: [
+    "grid-row-start",
+    "grid-column-start",
+    "grid-row-end",
+    "grid-column-end"
+  ],
+  initial_values: [
+    "auto",
+    "auto / auto",
+    "auto / auto / auto",
+    "auto / auto / auto / auto"
+  ],
+  other_values: gridAreaOtherValues,
+  invalid_values: gridAreaInvalidValues
+};
+
+gCSSProperties["grid-column-gap"] = {
+  domProp: "gridColumnGap",
+  inherited: false,
+  type: CSS_TYPE_LONGHAND,
+  initial_values: [ "0" ],
+  other_values: [ "2px", "2%", "1em", "calc(1px + 1em)", "calc(1%)",
+                  "calc(1% + 1ch)" , "calc(1px - 99%)" ],
+  invalid_values: [ "-1px", "auto", "none", "1px 1px", "-1%", "fit-content(1px)" ],
+};
+gCSSProperties["grid-row-gap"] = {
+  domProp: "gridRowGap",
+  inherited: false,
+  type: CSS_TYPE_LONGHAND,
+  initial_values: [ "0" ],
+  other_values: [ "2px", "2%", "1em", "calc(1px + 1em)", "calc(1%)",
+                  "calc(1% + 1ch)" , "calc(1px - 99%)" ],
+  invalid_values: [ "-1px", "auto", "none", "1px 1px", "-1%", "min-content" ],
+};
+gCSSProperties["grid-gap"] = {
+  domProp: "gridGap",
+  inherited: false,
+  type: CSS_TYPE_TRUE_SHORTHAND,
+  subproperties: [ "grid-column-gap", "grid-row-gap" ],
+  initial_values: [ "0", "0 0" ],
+  other_values: [ "1ch 0", "1px 1%", "1em 1px", "calc(1px) calc(1%)" ],
+  invalid_values: [ "-1px", "1px -1px", "1px 1px 1px", "inherit 1px",
+                    "1px auto" ]
+};
 
 if (IsCSSPropertyPrefEnabled("layout.css.contain.enabled")) {
   gCSSProperties["contain"] = {
diff --git a/layout/style/test/test_transitions_per_property.html b/layout/style/test/test_transitions_per_property.html
index eda160d95716..3fbfaae677a5 100644
--- a/layout/style/test/test_transitions_per_property.html
+++ b/layout/style/test/test_transitions_per_property.html
@@ -2012,9 +2012,6 @@ function test_font_weight(prop) {
 }
 
 function test_grid_gap(prop) {
-  if (!SpecialPowers.getBoolPref("layout.css.grid.enabled")) {
-    return;
-  }
   test_length_transition(prop);
   test_length_clamped(prop);
   test_percent_transition(prop);
diff --git a/modules/libpref/init/all.js b/modules/libpref/init/all.js
index 358ceb292236..74008448ab5d 100644
--- a/modules/libpref/init/all.js
+++ b/modules/libpref/init/all.js
@@ -3024,9 +3024,6 @@ pref("layout.css.all-shorthand.enabled", true);
 // Is support for CSS overflow-clip-box enabled for non-UA sheets?
 pref("layout.css.overflow-clip-box.enabled", false);
 
-// Is support for CSS grid enabled?
-pref("layout.css.grid.enabled", true);
-
 // Is support for CSS "grid-template-{columns,rows}: subgrid X" enabled?
 pref("layout.css.grid-template-subgrid-value.enabled", false);
 
