Most people opt for the worst-in-class and abuse phpbb as a public bug tracker. Especially in the game dev scene you'll see 99% of people doing this. It's a hilariously disgusting user experience for everyone involved, and by extension even for people who never touch it, because things easily get lost in there and never fixed/added.

Personally i use a combination of Uservoice and Github (if open) or otherwise find a way to make the internal bug tracker readable to the public.