From c7ddaa28120d675948197ef33c5d6eeace87aa65 Mon Sep 17 00:00:00 2001
From: Javan Makhmali <javan@javan.us>
Date: Sun, 9 Nov 2014 15:12:37 -0500
Subject: [PATCH] Guard against enabling the progress bar in unsupported
 browsers

Fix #429
Fix #426
---
 lib/assets/javascripts/turbolinks.js.coffee | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/assets/javascripts/turbolinks.js.coffee b/lib/assets/javascripts/turbolinks.js.coffee
index fc9cda31..5e4d633c 100644
--- a/lib/assets/javascripts/turbolinks.js.coffee
+++ b/lib/assets/javascripts/turbolinks.js.coffee
@@ -42,6 +42,7 @@ enableTransitionCache = (enable = true) ->
   transitionCacheEnabled = enable
 
 enableProgressBar = (enable = true) ->
+  return unless browserSupportsTurbolinks
   if enable
     progressBar ?= new ProgressBar 'html'
   else