Error randomly shows up if you’re not logged in; meaning not logged in I have seen error and error free homepage too.

I was logged in and got it too.

Alas, their login page gives the same error: https://twitter.com/login

I get it both as logged in user and in incognito mode since at least 17:04 UTC. Probably different front-end servers.

I am/was logged in, still get the error.