diff --git a/app/assets/javascripts/admin/components/ace-editor.js.es6 b/app/assets/javascripts/admin/components/ace-editor.js.es6
index 01773d2cbf8..a03865c40ce 100644
--- a/app/assets/javascripts/admin/components/ace-editor.js.es6
+++ b/app/assets/javascripts/admin/components/ace-editor.js.es6
@@ -36,6 +36,7 @@ export default Ember.Component.extend({
 
     loadScript("/javascripts/ace/ace.js", { scriptTag: true }).then(() => {
       window.ace.require(['ace/ace'], loadedAce => {
+        if (!this.element || this.isDestroying || this.isDestroyed) { return; }
         const editor = loadedAce.edit(this.$('.ace')[0]);
 
         editor.setTheme("ace/theme/chrome");
diff --git a/app/assets/javascripts/discourse/lib/load-script.js.es6 b/app/assets/javascripts/discourse/lib/load-script.js.es6
index 4edc9a452ac..cc24df86de8 100644
--- a/app/assets/javascripts/discourse/lib/load-script.js.es6
+++ b/app/assets/javascripts/discourse/lib/load-script.js.es6
@@ -5,13 +5,16 @@ const _loading = {};
 function loadWithTag(path, cb) {
   const head = document.getElementsByTagName('head')[0];
 
+  let finished = false;
   let s = document.createElement('script');
   s.src = path;
-  if (Ember.Test) { Ember.Test.pendingAjaxRequests++; }
+  if (Ember.Test) {
+    Ember.Test.registerWaiter(() => finished);
+  }
   head.appendChild(s);
 
   s.onload = s.onreadystatechange = function(_, abort) {
-    if (Ember.Test) { Ember.Test.pendingAjaxRequests--; }
+    finished = true;
     if (abort || !s.readyState || s.readyState === "loaded" || s.readyState === "complete") {
       s = s.onload = s.onreadystatechange = null;
       if (!abort) {