Fix #2: Restart the browser. If a quick refresh did not address the Roblox HTTP error 503 service unavailable, your next move is to close and restart the web browser. Fix #3: Check Roblox server ...

Most games have a UI, and it needs to look good and be usable. Roblox has decided to up its UI game via a new “styling” feature that has just gone to beta.

Roblox is not perfect, but neither is any other game. Players may find that certain functions aren't working, like guns not firing in PUBG, animations going bad and the screen starting to pixalate.

Should all that fail, you’ll just need to sit tight, wait it out, and try again a few hours later. For persistent issues, raise the issue with Roblox themselves over on the official support page ...