User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:54.0) Gecko/20100101 Firefox/54.0 Build ID: 20170427091925 Steps to reproduce: Accessed https://tv.xfinity.com/ to play a recorded or live TV video. Actual results: Video would play but when I tried to stop playing the video by clicking in the large "X" or back button icon on the Xfinity TV screen Firefox becomes non-responsive and the picture after a few moments starts jumping up and down slightly. The only way to exit Firefox is to press the "X" on the top of the Windows 10 64bit page and it eventually responds. After Firefox quits the audio still plays on for about 20 seconds. The 64 bit version of Firefox works (except stuttering on my laptop). I tried doing a refresh of Firefox but got the same results. Occasionally I get a message that a script has become unresponsive on Xfinity TV when trying to terminate the 32 bit version while attempting to end playing content. Expected results: This video on Xfinity TV (32 bit) used to work and terminate normally. (I tried it last week without any problems). The only change I made was the latest small Creators Windows update. Windows 10 Creators was installed several weeks ago without any problems to Firefox. I am currently using Firefox (32bit) Beta 3.
I just tried Firefox 54 Beta 4 (32 bit) and Xfinity TV now works peoperly. I also notified Comcast of the problem so eitgher Firefox or Comcast corrected the problem. This issue can be closed.
Thanks for the follow up testing Paul!