From 48337f3203532ac41a06619ad39a43272a051e72 Mon Sep 17 00:00:00 2001
From: Ben Ogle <ogle.ben@gmail.com>
Date: Fri, 27 Sep 2013 11:41:57 -0700
Subject: [PATCH 1/2] Just check for display != 'none' for visilbility

---
 src/editor.coffee            | 2 +-
 src/jquery-extensions.coffee | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/editor.coffee b/src/editor.coffee
index f09e40935..50761d51f 100644
--- a/src/editor.coffee
+++ b/src/editor.coffee
@@ -1175,7 +1175,7 @@ class Editor extends View
   updateDisplay: (options={}) ->
     return unless @attached and @activeEditSession
     return if @activeEditSession.destroyed
-    unless @isVisible()
+    unless @isOnDom() and @isVisible()
       @redrawOnReattach = true
       return
 
diff --git a/src/jquery-extensions.coffee b/src/jquery-extensions.coffee
index 1b6e7f4fd..c5bb6b568 100644
--- a/src/jquery-extensions.coffee
+++ b/src/jquery-extensions.coffee
@@ -35,7 +35,7 @@ $.fn.isOnDom = ->
   @closest(document.body).length is 1
 
 $.fn.isVisible = ->
-  @is(':visible')
+  @length > 0 and @css('display') != 'none'
 
 $.fn.isDisabled = ->
   !!@attr('disabled')

From ce9920a9ff6906c6b3b9ee20a2154658d1cae181 Mon Sep 17 00:00:00 2001
From: Ben Ogle <ogle.ben@gmail.com>
Date: Fri, 27 Sep 2013 14:33:39 -0700
Subject: [PATCH 2/2] Use jquery's hidden code in our isHidden()

---
 src/jquery-extensions.coffee | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/src/jquery-extensions.coffee b/src/jquery-extensions.coffee
index c5bb6b568..c749b1ce5 100644
--- a/src/jquery-extensions.coffee
+++ b/src/jquery-extensions.coffee
@@ -35,7 +35,21 @@ $.fn.isOnDom = ->
   @closest(document.body).length is 1
 
 $.fn.isVisible = ->
-  @length > 0 and @css('display') != 'none'
+  !@isHidden()
+
+$.fn.isHidden = ->
+  # Implementation taken from jQuery's `:hidden` expression code:
+  # https://github.com/jquery/jquery/blob/master/src/css/hiddenVisibleSelectors.js
+  #
+  # We were using a pseudo selector: @is(':hidden'). But jQuery's pseudo
+  # selector code checks the element's webkitMatchesSelector, which is always
+  # false, and is really really really slow.
+
+  elem = this[0]
+
+  return null unless elem
+
+  elem.offsetWidth <= 0 and elem.offsetHeight <= 0
 
 $.fn.isDisabled = ->
   !!@attr('disabled')