diff --git a/dom/base/nsFocusManager.cpp b/dom/base/nsFocusManager.cpp
index 3a8cb2acd8b0..017e7470c5a9 100644
--- a/dom/base/nsFocusManager.cpp
+++ b/dom/base/nsFocusManager.cpp
@@ -1379,7 +1379,13 @@ nsFocusManager::AdjustWindowFocus(nsPIDOMWindow* aWindow,
 bool
 nsFocusManager::IsWindowVisible(nsPIDOMWindow* aWindow)
 {
-  if (!aWindow)
+  if (!aWindow || aWindow->IsFrozen())
+    return false;
+
+  // Check if the inner window is frozen as well. This can happen when a focus change
+  // occurs while restoring a previous page.
+  nsPIDOMWindow* innerWindow = aWindow->GetCurrentInnerWindow();
+  if (!innerWindow || innerWindow->IsFrozen())
     return false;
 
   nsCOMPtr<nsIDocShell> docShell = aWindow->GetDocShell();