wait for both window.MathJax and window.MathJax.onReady

common/test/acceptance/pages/lms/video/video.py

@@ -53,7 +53,8 @@ VIDEO_MENUS = {
 }
 
 
-@js_defined('window.Video', 'window.RequireJS.require', 'window.jQuery')
+@js_defined('window.Video', 'window.RequireJS.require', 'window.jQuery',
+            'window.MathJax', 'window.MathJax.isReady')
 class VideoPage(PageObject):
     """
     Video player in the courseware.

common/test/acceptance/pages/studio/video/video.py

@@ -80,7 +80,7 @@ DELAY = 0.5
 
 
 @js_defined('window.Video', 'window.RequireJS.require', 'window.jQuery', 'window.XModule', 'window.XBlock',
-            'window.MathJax.isReady')
+            'window.MathJax', 'window.MathJax.isReady')
 class VideoComponentPage(VideoPage):
     """
     CMS Video Component Page