From 07716cb1d7572f858702651e1ed9182533dfd941 Mon Sep 17 00:00:00 2001
From: wolfbeast <mcwerewolf@gmail.com>
Date: Thu, 13 Dec 2018 13:54:51 +0100
Subject: [PATCH] Avoid useless FrameNeedsReflow call.

---
 layout/forms/nsComboboxControlFrame.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/layout/forms/nsComboboxControlFrame.cpp b/layout/forms/nsComboboxControlFrame.cpp
index f69198cc78..5a94389395 100644
--- a/layout/forms/nsComboboxControlFrame.cpp
+++ b/layout/forms/nsComboboxControlFrame.cpp
@@ -1040,6 +1040,9 @@ nsComboboxControlFrame::HandleRedisplayTextEvent()
   mRedisplayTextEvent.Forget();
 
   ActuallyDisplayText(true);
+  if (!weakThis.IsAlive())
+    return;
+
   // XXXbz This should perhaps be eResize.  Check.
   PresContext()->PresShell()->FrameNeedsReflow(mDisplayFrame,
                                                nsIPresShell::eStyleChange,