diff --git a/mozilla/dom/src/base/nsJSEnvironment.cpp b/mozilla/dom/src/base/nsJSEnvironment.cpp
index 5e9e8a33c5a..508e984c9d2 100644
--- a/mozilla/dom/src/base/nsJSEnvironment.cpp
+++ b/mozilla/dom/src/base/nsJSEnvironment.cpp
@@ -417,6 +417,9 @@ nsJSContext::~nsJSContext()
                               this);
   }
 
+  // Release mGlobalWrapperRef before the context is destroyed
+  mGlobalWrapperRef = nsnull;
+
   // Let xpconnect destroy the JSContext when it thinks the time is right.
   nsCOMPtr<nsIXPConnect> xpc(do_GetService(nsIXPConnect::GetCID()));
   if (xpc) {
@@ -1103,12 +1106,12 @@ nsJSContext::InitContext(nsIScriptGlobalObject *aGlobalObject)
 
   JSObject *global = ::JS_GetGlobalObject(mContext);
 
+  nsCOMPtr<nsIXPConnectJSObjectHolder> holder;
+
   // If there's already a global object in mContext we won't tell
   // XPConnect to wrap aGlobalObject since it's already wrapped.
 
   if (!global) {
-    nsCOMPtr<nsIXPConnectJSObjectHolder> holder;
-
     rv = xpc->InitClassesWithNewWrappedGlobal(mContext, aGlobalObject,
                                               NS_GET_IID(nsISupports),
                                               PR_FALSE,
@@ -1125,8 +1128,6 @@ nsJSContext::InitContext(nsIScriptGlobalObject *aGlobalObject)
     nsCOMPtr<nsIClassInfo> ci(do_QueryInterface(aGlobalObject));
 
     if (ci) {
-      nsCOMPtr<nsIXPConnectJSObjectHolder> holder;
-
       rv = xpc->WrapNative(mContext, global, aGlobalObject,
                            NS_GET_IID(nsISupports),
                            getter_AddRefs(holder));
@@ -1140,6 +1141,11 @@ nsJSContext::InitContext(nsIScriptGlobalObject *aGlobalObject)
     }
   }
 
+  // Hold a strong reference to the wrapper for the global to avoid
+  // rooting and unrooting the global object every time its AddRef()
+  // or Release() methods are called
+  mGlobalWrapperRef = holder;
+
   rv = InitClasses(); // this will complete global object initialization
   NS_ENSURE_SUCCESS(rv, rv);
 
diff --git a/mozilla/dom/src/base/nsJSEnvironment.h b/mozilla/dom/src/base/nsJSEnvironment.h
index 3d626c7aeed..09c4801b440 100644
--- a/mozilla/dom/src/base/nsJSEnvironment.h
+++ b/mozilla/dom/src/base/nsJSEnvironment.h
@@ -145,10 +145,17 @@ private:
   PRPackedBool mIsInitialized;
   PRPackedBool mScriptsEnabled;
   PRPackedBool mGCOnDestruction;
+  PRPackedBool mProcessingScriptTag;
 
   PRUint32 mBranchCallbackCount;
   PRUint32 mDefaultJSOptions;
-  PRBool mProcessingScriptTag;
+
+  // mGlobalWrapperRef is used only to hold a strong reference to the
+  // global object wrapper while the nsJSContext is alive. This cuts
+  // down on the number of rooting and unrooting calls XPConnect has
+  // to make when the global object is touched in JS.
+
+  nsCOMPtr<nsISupports> mGlobalWrapperRef;
 
   static int PR_CALLBACK JSOptionChangedCallback(const char *pref, void *data);