158.0.1 Constant logouts from xfinity.com/stream in windows new, works in Chrome

[kzbd]

That's it, starting a week ago I'm getting logged out of xfinity streaming constantly. I did some trouble shooting with google AI and hasn't worked. changed anything. Firefox on this machine used to stay logged in between windows sessions for months, now when I click to another tab or application I'm logged out immediately.

• Cleared Xfinity Cache and Cookies: Wiped the stored local tokens via the new Shield icon 🛡️ menu to rule out corrupted session data.
• Fixed the Bookmark URL: Deleted the deep link (/stream/home) and tested using the clean root URL (://xfinity.com) to prevent broken redirect handshakes.
• Turned Off Enhanced Tracking Protection: Switched the tracking shields off for Xfinity to stop Firefox from blocking background scripts.
• Adjusted Global Cookie Protections: Tested changing the dropdown to Allow all cookies to see if Firefox's strict container isolation was blocking the session.
• Added Explicit Exceptions: Formally whitelisted both https://xfinity.com and https://comcast.net (the hidden domain Xfinity uses to pass stream tokens) under Firefox’s privacy exceptions list.
• Prevented Background Tab Sleeping: Modified Firefox's hidden configurations (about:config) by toggling browser.tabs.unloadOnLowMemory and media.block-autoplay-until-in-foreground to false to force inactive tabs to stay awake.

[dftf]

@kzbd : try using the site in Troubleshoot Mode.  You access this in Menu -> Help and Report.

If it works fine there, it'll usually point to an extension causing the issue -- or possibly an about:config change you might have made in the past.

Also go to Menu -> Extensions and Themes -> Plugins and check the "OpenH264" and "Widevine" components are listed (not saying "waiting to install").  Tap the "..." on each one and make sure it is set there to "Always activate".

Also, if you use a VPN to access those services (i.e. live outside the US), that may also be the issue.

[sacdad]

I have tried this in Trouble shoot mode and it still as this issues as kzbd is talking about. Very annoying, hopefully a fix is forthcoming for this problem