There are a few ways to get in touch with the Libravatar developers:
Matrix or IRC
Join the #libravatar room via Matrix. Once you have joined the room, you will be able to see the conversation history from that point forward, even if you don't stay online.
IRC users can reach the same channel via Freenode IRC or an IRC web interface.
Please keep in mind that you may live in a different timezone than most of the developers. So if you don't get a response, it's not because we're ignoring you, it's probably because we're sleeping
Bug tracker
If you have a question about a particular bug, or some feedback on it, the best thing to do is to comment on that bug itself.
We use Gitlab as our bug tracker.
Mailing list
If you've got a proposal to discuss or prefer to write to us, you can join our developers mailing list.
Micro-blogging
Finally, you can also put short notices to our attention on Identica, Twitter or Mastodon.
And if you need to email us: dev@libravatar.org