Ask HN: Public Bug Tracking Best Practices

We've been proactive in asking our users for feedback on our startup's webapp experience at Mighty Spring (https://www.mightyspring.com/getstarted), but find that it's a bear to catch users up on which issues we already know about, so that we can get to whatever truly new insights they have.

We'd like something that is low-friction to start using — ideally where you don't have to sign up for a new service to be able to record a new complaint or upvote an existing one. Perhaps only requiring the entry of an email address?

I'm curious to hear what other HN readers do for bug tracking publicly, and how they facilitate communication about bugs across their user base.