From 5cb4b5f93bb8854748a0317f2f38b34add528a56 Mon Sep 17 00:00:00 2001
From: Hiroyuki Inoue <mammymax@gmail.com>
Date: Mon, 26 Jun 2017 15:40:21 -0700
Subject: [PATCH] Find compatibility of MutationObserver. Don't observe, if not
 found

---
 app/assets/javascripts/kuroko2/instance_linker.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/app/assets/javascripts/kuroko2/instance_linker.js b/app/assets/javascripts/kuroko2/instance_linker.js
index fd61c3a5..a31b90eb 100644
--- a/app/assets/javascripts/kuroko2/instance_linker.js
+++ b/app/assets/javascripts/kuroko2/instance_linker.js
@@ -1,4 +1,8 @@
 jQuery(function ($) {
+  var MutationObserver = window.MutationObserver || window.WebKitMutationObserver || window.MozMutationObserver;
+  if (!MutationObserver) {
+    return;
+  }
   var logParent = document.querySelector('#logs tbody');
   var observer = new MutationObserver(function(mutations) {
     if (mutations.some(function(m) {