I had the same problems connecting as you and others have had, i.e. the Roku keeps closing the hotel/dorm page before I could connect to Xfinity WiFi. So I took your approach a little further. I closed all apps on my iPhone so nothing would be trying to access the internet through the Roku. Then I turned off cellular data (Settings>Cellular>Cellular Data) so there would only be one network connection to my phone. Then I connected to the Roku’s temporary wifi connection (DIRECT-roku-xxx-xxxxxx) and was finally able to get the log in page to stay up long enough to connect to Xfinity WiFi.
Thank you so very much,been trying to figure out that problem for the longest and this actually worked. Just gotta choose the hotel or college dorm instead of home then go to your network settings on your phone or any other device and follow the instructions and it’ll take you to the xfinity browser.
I get about 3 seconds.. I need some help
So this what i did in order for it to work and get enough time to login after i press at a hotel or dorm... I removed all network passwords so nothing tries to connect and I set my phone on airplane mode. I then connected and was able to login with enough time.