I got that working with Karabiner Elements but how do people get this to work on Windows and Linux?

KMonad supports customisations like that. It's cross platform (macOS, Linux, Windows).

Though I use a fancy keyboard with QMK firmware, which allows customising this without needing to change settings on the computer.

I do it with xmodmap on Linux.

Did you change your username? I didn't realize that was an option.

Yes I did, and it probably wasn't really an option, but the moderators were kind enough to reclaim a very old, unused username (which I think was mine but forgot all the credentials to).

It's listed explicitly as an option in the FAQ.

What made you want to change it?

It's Stavros everywhere, it was only StavrosK here because the former was unavailable. I wasn't too fussed either way, but I asked the mods whether I could reclaim the username and they renamed the account to it, so here we are!

I figure it's easier for people to remember now.