Ask HN: What are some challenges found when moving from GitHub to GitLab?

I've been running https://www.gitignore.io for almost 6 years now. A few weeks ago, I built a project on GitLab and my experience was amazing. Integrated CI and Pipelines, private repos, the way GitLab provides transparency for its static site generator, The process for SSL secreting your site, and the extra features of GitLab Flavored Markdown were all better than GitHub.

One of the main reasons I'm sticking with GitHub is the community. It has taken 6 years to get to 4k stars and get a decent level of credibility and moving to GitLab would force me to start over. Including community, what other challenges have people found when migrating a project from GitHub to GitLab?