Dunno if entirely accurate but regarding the Firefox error:
“Twitter switched their top level domain to X, but didn't change any of their other domains, so they're still pulling assets from Twimg. Which makes Firefox (correctly) block the page if you have Tracking Protect enabled because it sees X trying to involve 3rd parties.“
You don't have to turn tracking protection off globally. You can leave it enabled in "strict" mode, and add the x.com domain as an exception (click the Manage Exceptions... button above the mode selection).
If you also use Privacy Badger, you'll have to center the slider for twitter.com when on the x.com login page.
You may not be happy with these compromises, but the above steps are tested and working for me. I have my primary Firefox profile set to delete all cookies on close but I do not log in to Twitter using that profile. I use Twitter in a second Firefox profile which keeps twitter.com/x.com cookies on close. If I want to open a third-party link someone tweeted, I just click and drag it from the Twitter profile window to my primary Firefox instance window. This is good enough privacy for me.
To make using multiple profiles at the same time easier, create custom desktop launchers for secondary profiles and give them a different theme. This is simple on GNOME and most likely possible on other desktop environments and OSs as well.
It is somewhat ironic that one bad decision (firing everyone) has delayed the impact of another bad decision (surely the worst rebrand since, at least, New Coke).
From the top of my head: large-format posts, spaces, improvements in video hosting (can post multiple hours), community notes is now an integral part, premium accounts.
> large-format posts, spaces, improvements in video hosting (can post multiple hours), community notes is now an integral part, premium accounts.
All features that existed before the change in ownership. They had increases in length or branding changes but already had the core framework implemented.
“Twitter switched their top level domain to X, but didn't change any of their other domains, so they're still pulling assets from Twimg. Which makes Firefox (correctly) block the page if you have Tracking Protect enabled because it sees X trying to involve 3rd parties.“
Slow clap.