--- a/dom/base/nsGlobalWindow.cpp
+++ b/dom/base/nsGlobalWindow.cpp
@@ -2694,16 +2694,17 @@ nsGlobalWindow::SetNewDocument(nsIDocume
       mArguments = nullptr;
     }
 
     // Give the new inner window our chrome event handler (since it
     // doesn't have one).
     newInnerWindow->mChromeEventHandler = mChromeEventHandler;
   }
 
+  nsJSContext::PokeGC(JS::gcreason::SET_NEW_DOCUMENT);
   mContext->DidInitializeContext();
 
   // We wait to fire the debugger hook until the window is all set up and hooked
   // up with the outer. See bug 969156.
   if (createdInnerWindow) {
     // AutoEntryScript required to invoke debugger hook, which is a
     // Gecko-specific concept at present.
     AutoEntryScript aes(newInnerWindow);