It’s easy to find the email addresses of Quod Libet’s authors and maintainers, but please don’t email us directly unless asked to, or if it concerns us specifically. If you contact just us, it means no one else can help you, and we can be really bad about replying to email.
The best way to report bugs is using the GitHub issue tracker.
For tips on how to report bugs see the Contributing Guide
If you’re not sure if the behavior is a bug, or if you have other questions, the best way to contact us is through the quod-libet-devel Google group.