diff --git a/dom/base/nsJSEnvironment.cpp b/dom/base/nsJSEnvironment.cpp
index 0c8b0f6905ef..a177e3eca758 100644
--- a/dom/base/nsJSEnvironment.cpp
+++ b/dom/base/nsJSEnvironment.cpp
@@ -2090,10 +2090,15 @@ CCRunnerFired(TimeStamp aDeadline, void* aData)
         // Our efforts to avoid a CC have failed, so we return to let the
         // timer fire once more to trigger a CC.
 
-        // Clear content unbinder before the first CC slice.
-        Element::ClearContentUnbinder();
-        // And trigger deferred deletion too.
-        nsCycleCollector_doDeferredDeletion();
+        if (!aDeadline.IsNull() && TimeStamp::Now() < aDeadline) {
+          // Clear content unbinder before the first CC slice.
+          Element::ClearContentUnbinder();
+
+          if (TimeStamp::Now() < aDeadline) {
+            // And trigger deferred deletion too.
+            nsCycleCollector_doDeferredDeletion();
+          }
+        }
         return didDoWork;
       }
     } else {
diff --git a/js/xpconnect/src/XPCJSRuntime.cpp b/js/xpconnect/src/XPCJSRuntime.cpp
index f16c4bc6829b..a6c49cc85b9e 100644
--- a/js/xpconnect/src/XPCJSRuntime.cpp
+++ b/js/xpconnect/src/XPCJSRuntime.cpp
@@ -140,7 +140,7 @@ public:
   nsresult Dispatch()
   {
       nsCOMPtr<nsIRunnable> self(this);
-      return NS_IdleDispatchToCurrentThread(self.forget(), 1000);
+      return NS_IdleDispatchToCurrentThread(self.forget(), 2500);
   }
 
   void Start(bool aContinuation = false, bool aPurge = false)