From 8c4c21dae92f58ef457b6f0c98b79dd7ccf96c3c Mon Sep 17 00:00:00 2001
From: Edgar Chen <echen@mozilla.com>
Date: Mon, 9 Nov 2020 14:57:54 +0000
Subject: [PATCH] Bug 1676127 - Don't deactivate top-level remote browser twice
 when browser window is lowered; r=hsivonen

Differential Revision: https://phabricator.services.mozilla.com/D96404
---
 dom/base/nsFocusManager.cpp | 23 +++++++++--------------
 1 file changed, 9 insertions(+), 14 deletions(-)

diff --git a/dom/base/nsFocusManager.cpp b/dom/base/nsFocusManager.cpp
index bf73fe8482b5..419fa14a68bb 100644
--- a/dom/base/nsFocusManager.cpp
+++ b/dom/base/nsFocusManager.cpp
@@ -2226,26 +2226,21 @@ bool nsFocusManager::BlurImpl(BrowsingContext* aBrowsingContextToClear,
     // content
     if (BrowserParent* remote = BrowserParent::GetFrom(element)) {
       MOZ_ASSERT(XRE_IsParentProcess());
-      // First, let's deactivate all out-of-process iframes.
+      // Let's deactivate all remote browsers.
       BrowsingContext* topLevelBrowsingContext = remote->GetBrowsingContext();
       topLevelBrowsingContext->PreOrderWalk([&](BrowsingContext* aContext) {
-        WindowGlobalParent* windowGlobalParent =
-            aContext->Canonical()->GetCurrentWindowGlobal();
-        if (windowGlobalParent) {
-          RefPtr<BrowserParent> browserParent =
-              windowGlobalParent->GetBrowserParent();
-          if (browserParent) {
+        if (WindowGlobalParent* windowGlobalParent =
+                aContext->Canonical()->GetCurrentWindowGlobal()) {
+          if (RefPtr<BrowserParent> browserParent =
+                  windowGlobalParent->GetBrowserParent()) {
             browserParent->Deactivate(windowBeingLowered);
-            LOGFOCUS(("OOP iframe remote browser deactivated %p, %d", remote,
-                      windowBeingLowered));
+            LOGFOCUS(("%s remote browser deactivated %p, %d",
+                      aContext == topLevelBrowsingContext ? "Top-level"
+                                                          : "OOP iframe",
+                      browserParent.get(), windowBeingLowered));
           }
         }
       });
-
-      // Now deactivate the top-level Web page.
-      remote->Deactivate(windowBeingLowered);
-      LOGFOCUS(("Top-level Remote browser deactivated %p, %d", remote,
-                windowBeingLowered));
     }
 
     // Same as above but for out-of-process iframes