--- a/layout/style/nsCSSParser.cpp
+++ b/layout/style/nsCSSParser.cpp
@@ -14890,24 +14890,24 @@ CSSParserImpl::ParseTextAlign(nsCSSValue
   if (!nsLayoutUtils::IsTextAlignTrueValueEnabled()) {
     aValue = left;
     return true;
   }
 
   nsCSSValue right;
   if (ParseSingleTokenVariant(right, VARIANT_KEYWORD, aTable)) {
     // 'true' must be combined with some other value than 'true'.
-    if (left.GetIntValue() == NS_STYLE_TEXT_ALIGN_TRUE &&
-        right.GetIntValue() == NS_STYLE_TEXT_ALIGN_TRUE) {
+    if (left.GetIntValue() == NS_STYLE_TEXT_ALIGN_UNSAFE &&
+        right.GetIntValue() == NS_STYLE_TEXT_ALIGN_UNSAFE) {
       return false;
     }
     aValue.SetPairValue(left, right);
   } else {
     // Single value 'true' is not allowed.
-    if (left.GetIntValue() == NS_STYLE_TEXT_ALIGN_TRUE) {
+    if (left.GetIntValue() == NS_STYLE_TEXT_ALIGN_UNSAFE) {
       return false;
     }
     aValue = left;
   }
   return true;
 }
 
 bool

--- a/layout/style/nsCSSProps.cpp
+++ b/layout/style/nsCSSProps.cpp
@@ -1954,30 +1954,30 @@ KTableEntry nsCSSProps::kTextAlignKTable
   { eCSSKeyword_right, NS_STYLE_TEXT_ALIGN_RIGHT },
   { eCSSKeyword_center, NS_STYLE_TEXT_ALIGN_CENTER },
   { eCSSKeyword_justify, NS_STYLE_TEXT_ALIGN_JUSTIFY },
   { eCSSKeyword__moz_center, NS_STYLE_TEXT_ALIGN_MOZ_CENTER },
   { eCSSKeyword__moz_right, NS_STYLE_TEXT_ALIGN_MOZ_RIGHT },
   { eCSSKeyword__moz_left, NS_STYLE_TEXT_ALIGN_MOZ_LEFT },
   { eCSSKeyword_start, NS_STYLE_TEXT_ALIGN_DEFAULT },
   { eCSSKeyword_end, NS_STYLE_TEXT_ALIGN_END },
-  { eCSSKeyword_unsafe, NS_STYLE_TEXT_ALIGN_TRUE },
+  { eCSSKeyword_unsafe, NS_STYLE_TEXT_ALIGN_UNSAFE },
   { eCSSKeyword_match_parent, NS_STYLE_TEXT_ALIGN_MATCH_PARENT },
   { eCSSKeyword_UNKNOWN, -1 }
 };
 
 KTableEntry nsCSSProps::kTextAlignLastKTable[] = {
   { eCSSKeyword_auto, NS_STYLE_TEXT_ALIGN_AUTO },
   { eCSSKeyword_left, NS_STYLE_TEXT_ALIGN_LEFT },
   { eCSSKeyword_right, NS_STYLE_TEXT_ALIGN_RIGHT },
   { eCSSKeyword_center, NS_STYLE_TEXT_ALIGN_CENTER },
   { eCSSKeyword_justify, NS_STYLE_TEXT_ALIGN_JUSTIFY },
   { eCSSKeyword_start, NS_STYLE_TEXT_ALIGN_DEFAULT },
   { eCSSKeyword_end, NS_STYLE_TEXT_ALIGN_END },
-  { eCSSKeyword_unsafe, NS_STYLE_TEXT_ALIGN_TRUE },
+  { eCSSKeyword_unsafe, NS_STYLE_TEXT_ALIGN_UNSAFE },
   { eCSSKeyword_UNKNOWN, -1 }
 };
 
 const KTableEntry nsCSSProps::kTextCombineUprightKTable[] = {
   { eCSSKeyword_none, NS_STYLE_TEXT_COMBINE_UPRIGHT_NONE },
   { eCSSKeyword_all, NS_STYLE_TEXT_COMBINE_UPRIGHT_ALL },
   { eCSSKeyword_digits, NS_STYLE_TEXT_COMBINE_UPRIGHT_DIGITS_2 }, // w/o number ==> 2
   { eCSSKeyword_UNKNOWN, -1 }

--- a/layout/style/nsRuleNode.cpp
+++ b/layout/style/nsRuleNode.cpp
@@ -4387,17 +4387,17 @@ nsRuleNode::ComputeTextData(void* aStart
     }
   } else {
     if (eCSSUnit_Pair == textAlignValue->GetUnit()) {
       // Two values were specified, one must be 'true'.
       text->mTextAlignTrue = true;
       const nsCSSValuePair& textAlignValuePair = textAlignValue->GetPairValue();
       textAlignValue = &textAlignValuePair.mXValue;
       if (eCSSUnit_Enumerated == textAlignValue->GetUnit()) {
-        if (textAlignValue->GetIntValue() == NS_STYLE_TEXT_ALIGN_TRUE) {
+        if (textAlignValue->GetIntValue() == NS_STYLE_TEXT_ALIGN_UNSAFE) {
           textAlignValue = &textAlignValuePair.mYValue;
         }
       } else if (eCSSUnit_String == textAlignValue->GetUnit()) {
         NS_NOTYETIMPLEMENTED("align string");
       }
     } else if (eCSSUnit_Inherit == textAlignValue->GetUnit() ||
                eCSSUnit_Unset == textAlignValue->GetUnit()) {
       text->mTextAlignTrue = parentText->mTextAlignTrue;
@@ -4412,17 +4412,17 @@ nsRuleNode::ComputeTextData(void* aStart
   const nsCSSValue* textAlignLastValue = aRuleData->ValueForTextAlignLast();
   text->mTextAlignLastTrue = false;
   if (eCSSUnit_Pair == textAlignLastValue->GetUnit()) {
     // Two values were specified, one must be 'true'.
     text->mTextAlignLastTrue = true;
     const nsCSSValuePair& textAlignLastValuePair = textAlignLastValue->GetPairValue();
     textAlignLastValue = &textAlignLastValuePair.mXValue;
     if (eCSSUnit_Enumerated == textAlignLastValue->GetUnit()) {
-      if (textAlignLastValue->GetIntValue() == NS_STYLE_TEXT_ALIGN_TRUE) {
+      if (textAlignLastValue->GetIntValue() == NS_STYLE_TEXT_ALIGN_UNSAFE) {
         textAlignLastValue = &textAlignLastValuePair.mYValue;
       }
     }
   } else if (eCSSUnit_Inherit == textAlignLastValue->GetUnit() ||
              eCSSUnit_Unset == textAlignLastValue->GetUnit()) {
     text->mTextAlignLastTrue = parentText->mTextAlignLastTrue;
   }
   SetDiscrete(*textAlignLastValue, text->mTextAlignLast,

--- a/layout/style/nsStyleConsts.h
+++ b/layout/style/nsStyleConsts.h
@@ -804,17 +804,17 @@ enum class FillMode : uint32_t;
 #define NS_STYLE_TEXT_ALIGN_END                   6
 #define NS_STYLE_TEXT_ALIGN_AUTO                  7
 #define NS_STYLE_TEXT_ALIGN_MOZ_CENTER            8
 #define NS_STYLE_TEXT_ALIGN_MOZ_RIGHT             9
 #define NS_STYLE_TEXT_ALIGN_MOZ_LEFT             10
 // NS_STYLE_TEXT_ALIGN_MOZ_CENTER_OR_INHERIT is only used in data structs; it
 // is never present in stylesheets or computed data.
 #define NS_STYLE_TEXT_ALIGN_MOZ_CENTER_OR_INHERIT 11
-#define NS_STYLE_TEXT_ALIGN_TRUE                  12
+#define NS_STYLE_TEXT_ALIGN_UNSAFE                12
 #define NS_STYLE_TEXT_ALIGN_MATCH_PARENT          13
 // Note: make sure that the largest NS_STYLE_TEXT_ALIGN_* value is smaller than
 // the smallest NS_STYLE_VERTICAL_ALIGN_* value below!
 
 // See nsStyleText, nsStyleFont
 #define NS_STYLE_TEXT_DECORATION_LINE_NONE         0
 #define NS_STYLE_TEXT_DECORATION_LINE_UNDERLINE    0x01
 #define NS_STYLE_TEXT_DECORATION_LINE_OVERLINE     0x02