1 files changed, 16 insertions, 0 deletions
diff --git a/editor/libeditor/HTMLEditorEventListener.cpp b/editor/libeditor/HTMLEditorEventListener.cpp
index c4d857908..a22188483 100644
--- a/editor/libeditor/HTMLEditorEventListener.cpp
+++ b/editor/libeditor/HTMLEditorEventListener.cpp
@@ -53,6 +53,12 @@ HTMLEditorEventListener::GetHTMLEditor()
 nsresult
 HTMLEditorEventListener::MouseUp(nsIDOMMouseEvent* aMouseEvent)
 {
+  if (DetachedFromEditor()) {
+    return NS_OK;
+  }
+
+  // FYI: We need to notify HTML editor of mouseup even if it's consumed
+  //      because HTML editor always needs to release grabbing resizer.
   HTMLEditor* htmlEditor = GetHTMLEditor();
 
   nsCOMPtr<nsIDOMEventTarget> target;
@@ -72,6 +78,10 @@ HTMLEditorEventListener::MouseUp(nsIDOMMouseEvent* aMouseEvent)
 nsresult
 HTMLEditorEventListener::MouseDown(nsIDOMMouseEvent* aMouseEvent)
 {
+  if (NS_WARN_IF(!aMouseEvent) || DetachedFromEditor()) {
+    return NS_OK;
+  }
+
   WidgetMouseEvent* mousedownEvent =
     aMouseEvent->AsEvent()->WidgetEventPtr()->AsMouseEvent();
 
@@ -86,6 +96,9 @@ HTMLEditorEventListener::MouseDown(nsIDOMMouseEvent* aMouseEvent)
     return EditorEventListener::MouseDown(aMouseEvent);
   }
 
+  // XXX This method may change selection. So, we need to commit composition
+  //     here, first.
+
   // Detect only "context menu" click
   // XXX This should be easier to do!
   // But eDOMEvents_contextmenu and eContextMenu is not exposed in any event
@@ -179,6 +192,9 @@ HTMLEditorEventListener::MouseDown(nsIDOMMouseEvent* aMouseEvent)
         } else {
           htmlEditor->SelectElement(element);
         }
+        if (DetachedFromEditor()) {
+          return NS_OK;
+        }
       }
     }
     // HACK !!! Context click places the caret but the context menu consumes