Oh so that's why haha Then my swedish intuition wasn't completely off.
No worries at all. It is a bit of self-deprecating humor. I learned the term from my Swedish (ex)girlfriend's family. If they tasted something at an english speaking house that they wanted to warn the others tasted bad they would say "Very nice, fogelbise" and explained to me that it meant bird poop, so I thought it would be a funny user name but spelled it how it sounded in English.
Hi fogelbise. I don't mean this to be offensive I think it's a funny coincidence. What does your name mean? Tell me cause I need to stop reading it as "birdpoop". That's what "fågelbajs" means in my native language and it's pronounced the same xD