Push to a remote repository will delete any branch on the target that is not on the source
Example:
Omnibus-gitlab repository on gitlab.com has mirroring setup to push to the repository on dev.gitlab.org.
If a new branch gets pushed to dev.gitlab.org, on the next sync repository mirror will remove the branch.
If we consider this setup a full sync then it is not unusual that the source project is the single source of truth.
However, deleting a branch could be also considered as data loss.
Reading the Mirror page this is not obvious and it might bite our customers/users.
@rdavila @DouweM @rspeicher Any ideas how to improve this?