Firefox’s Enhanced Tracking Protection (Strict Mode) is known to cause issues on x.com
There were no “issues”; everything was working completely fine. This is a deliberate decision to force people to turn off tracking protection.
I saw a recommendation to use Firefox’s container extension https://support.mozilla.org/en-US/kb/containers, but it’s disabled in private browsing windows, and I always use private browsing windows.
But it directly says to disable enhanced tracking protection. Weird fuck up.
Yes, confirmed it now works again on Firefox Mobile. Today was the day where they switched over the domain, so I guess that makes sense.