diff --git a/dom/base/nsGkAtomList.h b/dom/base/nsGkAtomList.h
index 75c031afac..af25f97e1c 100644
--- a/dom/base/nsGkAtomList.h
+++ b/dom/base/nsGkAtomList.h
@@ -39,6 +39,7 @@ GK_ATOM(_moz_resizing, "_moz_resizing")
 GK_ATOM(mozallowfullscreen, "mozallowfullscreen")
 GK_ATOM(moztype, "_moz-type")
 GK_ATOM(mozdirty, "_moz_dirty")
+GK_ATOM(_is_cropped, "_is_cropped")
 GK_ATOM(mozdisallowselectionprint, "mozdisallowselectionprint")
 GK_ATOM(mozdonotsend, "moz-do-not-send")
 GK_ATOM(mozeditorbogusnode, "_moz_editor_bogus_node")
diff --git a/layout/xul/nsTextBoxFrame.cpp b/layout/xul/nsTextBoxFrame.cpp
index 4c420f9323..755668d806 100644
--- a/layout/xul/nsTextBoxFrame.cpp
+++ b/layout/xul/nsTextBoxFrame.cpp
@@ -629,6 +629,10 @@ nsTextBoxFrame::CalculateTitleForWidth(nsRenderingContext& aRenderingContext,
 {
     DrawTarget* drawTarget = aRenderingContext.GetDrawTarget();
 
+    if (mContent->HasAttr(kNameSpaceID_None, nsGkAtoms::_is_cropped)) {
+        mContent->UnsetAttr(kNameSpaceID_None, nsGkAtoms::_is_cropped, true);
+    }
+
     if (mTitle.IsEmpty()) {
         mCroppedTitle.Truncate();
         return 0;
@@ -831,6 +835,9 @@ nsTextBoxFrame::CalculateTitleForWidth(nsRenderingContext& aRenderingContext,
         break;
     }
 
+    mContent->SetAttr(kNameSpaceID_None, nsGkAtoms::_is_cropped,
+                      NS_LITERAL_STRING("true"), true);
+
     return nsLayoutUtils::AppUnitWidthOfStringBidi(mCroppedTitle, this, *fm,
                                                    aRenderingContext);
 }