diff --git a/mozilla/xpcom/threads/nsTimerImpl.cpp b/mozilla/xpcom/threads/nsTimerImpl.cpp
index 5cdda285933..363733aaebc 100644
--- a/mozilla/xpcom/threads/nsTimerImpl.cpp
+++ b/mozilla/xpcom/threads/nsTimerImpl.cpp
@@ -577,7 +577,7 @@ NS_IMETHODIMP nsTimerManager::FireNextIdleTimer()
   if (count > 0) {
     nsTimerImpl *theTimer = NS_STATIC_CAST(nsTimerImpl*, NS_STATIC_CAST(nsITimer*, gIdleTimers->ElementAt(0))); // addrefs
 
-    gIdleTimers->RemoveElement(NS_STATIC_CAST(nsITimer*, theTimer));
+    gIdleTimers->RemoveElement(NS_STATIC_CAST(nsITimer*, theTimer), 0);
 
     theTimer->Fire();