I can not figure out why this happens. I tried to play around with all the permissions, reset printer settings on Firefox, created new profiles, all had the same problem. But when I used those same profiles on the apt installation it printed just fine. Is there some weird Flatpak sandboxing happening because I can print fine from the Ungoogled Chromium Flatpak but not Firefox Flatpak.
At launch it says
Failed to load module "xapp-gtk3-module"
/home/MyUsername/.mozilla/firefox/htzenoyk.Default User/user.js:1: prefs parse error: unexpected character
ATTENTION: default value of option mesa_glthread overridden by environment.
ATTENTION: default value of option mesa_glthread overridden by environment.
When I go to print and it crashes it says
ExceptionHandler::GenerateDump cloned child 797
ExceptionHandler::SendContinueSignalToChild sent continue signal to child
ExceptionHandler::WaitForContinueSignal waiting for continue signal...