diff --git a/dom/base/nsJSEnvironment.cpp b/dom/base/nsJSEnvironment.cpp
index 1efe9d425149..be44818df622 100644
--- a/dom/base/nsJSEnvironment.cpp
+++ b/dom/base/nsJSEnvironment.cpp
@@ -1392,6 +1392,7 @@ nsJSContext::ExecuteScript(JSScript* aScriptObject,
 
   nsJSContext::TerminationFuncHolder holder(this);
   XPCAutoRequest ar(mContext);
+  JSAutoCompartment ac(mContext, aScopeObject);
   ++mExecuteDepth;
 
   // The result of evaluation, used only if there were no errors. This need