Yeah, issues and comments (which can be quite important for a repository imo) are unfortunately not included in a git repository so migration of these is not trivial.
I will have to look this up. Thanks for your response!
Yeah they need to get backed up somehow. GitHub probably doesnt offer an API for that
Actually, it looks like they do have an API for that https://raw.githubusercontent.com/github/rest-api-description/main/descriptions-next/ghes-3.6/ghes-3.6.yaml
The repo owner shall file GDPR date export request to backup the issues once a month.
There was some discussion about this during Austin Bit Devs last month. I think there are several mirrors. A lot of the context is indeed on GitHub though.