From a0c72d1b9a584ed25f418717fa7966490aa2c3a6 Mon Sep 17 00:00:00 2001
From: Simon Lydell <simon.lydell@gmail.com>
Date: Fri, 23 Jan 2015 16:53:09 +0100
Subject: [PATCH] Fix #447: Regression: Hints generation crashes

Commit e1497ee accidentally removed the null check for `.getComputedStyle()` in
isElementVisible. This commit adds it back.
---
 extension/packages/utils.coffee | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/extension/packages/utils.coffee b/extension/packages/utils.coffee
index 5a98e96..0d4be4b 100644
--- a/extension/packages/utils.coffee
+++ b/extension/packages/utils.coffee
@@ -91,7 +91,9 @@ isElementGoogleEditable = (element) ->
 isElementVisible = (element) ->
   document = element.ownerDocument
   window   = document.defaultView
-  computedStyle = window.getComputedStyle(element, null)
+  # `.getComputedStyle()` may return `null` if the computed style isn’t
+  # availble yet. If so, consider the element not visible.
+  return false unless computedStyle = window.getComputedStyle(element, null)
   return computedStyle.getPropertyValue('visibility') == 'visible' and
          computedStyle.getPropertyValue('display') != 'none' and
          computedStyle.getPropertyValue('opacity') != '0'
-- 
2.39.3