From 4a9cd8fe06d414558cc256cc0a9277fbf8557317 Mon Sep 17 00:00:00 2001
From: Artem-Babich <51639399+Artem-Babich@users.noreply.github.com>
Date: Mon, 28 Mar 2022 13:02:32 +0400
Subject: [PATCH] fix: avoid focusing already removed iframe(closes #2178)

---
 src/client/sandbox/event/focus-blur.ts | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/client/sandbox/event/focus-blur.ts b/src/client/sandbox/event/focus-blur.ts
index d118cb365..a289e9acb 100644
--- a/src/client/sandbox/event/focus-blur.ts
+++ b/src/client/sandbox/event/focus-blur.ts
@@ -291,6 +291,11 @@ export default class FocusBlurSandbox extends SandboxBase {
                                    !styleUtils.isElementInInvisibleIframe(el);
         const elDocument         = (el[INTERNAL_PROPS.processedContext] || this.window).document;
 
+        // NOTE: In some cases focus event can be raised for the element in the iframe at the moment when the iframe is removed from the document.
+        // For example, in React application by its internal mechanism: https://github.com/DevExpress/testcafe-hammerhead/issues/2178
+        if(!elDocument.defaultView)
+            return null;
+
         if (!raiseEventInIframe || isNativeFocus && !styleUtils.isElementVisible(el, elDocument))
             return null;