Guess what, it's someone who just joined and is asking for help.

Whenever I try and play online, the game switches my normal profile name (Superfield) with the name of a gametype with a couple letters cut off (Classic Sla, Classic Eli, etc). It also adds this profile name to the list of gametypes, and it says I can't delete it because it's a default gametype. If I restart the game, however, I can delete it. It was working fine earlier today.

I've had this issue before. If you make a server in game (eg. LAN/Internet) and click on a classic non-editable gametype (eg. Classic Slayer) it makes a new profile and changes to a new one. From what I know the bug isn't patched and the only way to 'fix' it is to make a replica gametype of the default set.

The thing is is that it doesn't just happen when I start a server; for example, if I edit the server filters (which resets itself now, for some reason), and go back, the game flickers a little, I can see part of my desktop (which never happened before), and it changes my profile.

What UI map are you using?

Not sure what you mean by that. Default, I guess.