I'm an old user on this website. I wanted to join the Code Review community just now, so I clicked the "join this community" button on the top navbar, got a page with a fancy blue button so I click to confirm joining the community.
The first time I clicked the button, I got a "500" page containing some bold phrase saying "this is our fault." I repeated the process and I got a 404 instead.
I clicked over the home button and I saw myself joined in the community.
I have no idea what caused each of these errors. I would be happy to help debugging the issue if there's anything I can do.