--- a/widget/gtk/nsClipboard.cpp
+++ b/widget/gtk/nsClipboard.cpp
@@ -391,16 +391,18 @@ nsClipboard::HasDataMatchingFlavors(cons
 {
   if (!aFlavorList || !_retval)
       return NS_ERROR_NULL_POINTER;
 
   *_retval = false;
 
   int targetNums;
   GdkAtom* targets = mContext->GetTargets(aWhichClipboard, &targetNums);
+  if (!targets)
+      return NS_OK;
 
   // Walk through the provided types and try to match it to a
   // provided type.
   for (uint32_t i = 0; i < aLength && !*_retval; i++) {
       // We special case text/unicode here.
       if (!strcmp(aFlavorList[i], kUnicodeMime) &&
           gtk_targets_include_text(targets, targetNums)) {
           *_retval = true;