When Microsoft bought github and we moved to our own gitlab instance, it became much harder for people to contribute code to our projects. The biggest issue was that people couldn’t fork the repos anymore freely. You could still send merge requests from cli, but the process was not well known.
So, one solution might be to mirror out gitlab to either gitlab.com or github.com. This way users could freely fork our repos in gitlab/github and send merge requests to us. We would probably need bidirectional mirroring (Repository mirroring | GitLab), with only protected branches mirrored. However, this might lead to some fragmentation in issue tracking, when people would open issues both in github and gitlab.
Another option might be to explore local forking more thoroughly and make tutorial on how to use it?
One other thing we could do is to setup discourse as sso provider for gitlab, so people could open issues with their discourse credentials.
Any thoughts on this?