5 files changed, 19 insertions, 2 deletions
diff --git a/layout/generic/nsTextFrame.cpp b/layout/generic/nsTextFrame.cpp
index 4bc542626..a47b87e38 100644
--- a/layout/generic/nsTextFrame.cpp
+++ b/layout/generic/nsTextFrame.cpp
@@ -8245,6 +8245,17 @@ nsTextFrame::AddInlineMinISizeForFlow(nsRenderingContext *aRenderingContext,
     return;
   }
 
+  // If overflow-wrap is 'anywhere', we can wrap everywhere.
+  if (textStyle->mOverflowWrap == NS_STYLE_OVERFLOWWRAP_ANYWHERE &&
+      textStyle->WordCanWrap(this)) {
+    aData->OptionallyBreak();
+    aData->mCurrentLine +=
+      textRun->GetMinAdvanceWidth(Range(start, flowEndInTextRun));
+    aData->mTrailingWhitespace = 0;
+    aData->OptionallyBreak();
+    return;
+  }
+
   AutoTArray<bool,BIG_TEXT_NODE_SIZE> hyphBuffer;
   bool *hyphBreakBefore = nullptr;
   if (hyphenating) {
diff --git a/layout/style/nsCSSKeywordList.h b/layout/style/nsCSSKeywordList.h
index 9045da9ff..86ba59142 100644
--- a/layout/style/nsCSSKeywordList.h
+++ b/layout/style/nsCSSKeywordList.h
@@ -144,6 +144,7 @@ CSS_KEY(alternate, alternate)
 CSS_KEY(alternate-reverse, alternate_reverse)
 CSS_KEY(always, always)
 CSS_KEY(annotation, annotation)
+CSS_KEY(anywhere, anywhere)
 CSS_KEY(appworkspace, appworkspace)
 CSS_KEY(auto, auto)
 CSS_KEY(auto-fill, auto_fill)
diff --git a/layout/style/nsCSSProps.cpp b/layout/style/nsCSSProps.cpp
index 24c97cf33..e0cda2488 100644
--- a/layout/style/nsCSSProps.cpp
+++ b/layout/style/nsCSSProps.cpp
@@ -2284,6 +2284,7 @@ const KTableEntry nsCSSProps::kWordBreakKTable[] = {
 const KTableEntry nsCSSProps::kOverflowWrapKTable[] = {
   { eCSSKeyword_normal, NS_STYLE_OVERFLOWWRAP_NORMAL },
   { eCSSKeyword_break_word, NS_STYLE_OVERFLOWWRAP_BREAK_WORD },
+  { eCSSKeyword_anywhere, NS_STYLE_OVERFLOWWRAP_ANYWHERE },
   { eCSSKeyword_UNKNOWN, -1 }
 };
 
diff --git a/layout/style/nsStyleConsts.h b/layout/style/nsStyleConsts.h
index f54387aa8..e6a0cc65a 100644
--- a/layout/style/nsStyleConsts.h
+++ b/layout/style/nsStyleConsts.h
@@ -997,6 +997,7 @@ enum class StyleDisplay : uint8_t {
 // See nsStyleText
 #define NS_STYLE_OVERFLOWWRAP_NORMAL            0
 #define NS_STYLE_OVERFLOWWRAP_BREAK_WORD        1
+#define NS_STYLE_OVERFLOWWRAP_ANYWHERE          2
 
 // See nsStyleText
 #define NS_STYLE_HYPHENS_NONE                   0
diff --git a/layout/style/nsStyleStruct.h b/layout/style/nsStyleStruct.h
index f49cdc43e..cca7bb8d4 100644
--- a/layout/style/nsStyleStruct.h
+++ b/layout/style/nsStyleStruct.h
@@ -2134,8 +2134,11 @@ struct MOZ_NEEDS_MEMMOVABLE_MEMBERS nsStyleText
   }
 
   bool WordCanWrapStyle() const {
-    return WhiteSpaceCanWrapStyle() &&
-           mOverflowWrap == NS_STYLE_OVERFLOWWRAP_BREAK_WORD;
+    if (!WhiteSpaceCanWrapStyle()) {
+      return false;
+    }
+    return (mOverflowWrap == NS_STYLE_OVERFLOWWRAP_BREAK_WORD ||
+            mOverflowWrap == NS_STYLE_OVERFLOWWRAP_ANYWHERE);
   }
 
   bool HasTextEmphasis() const {