While this may be broadly true, if I remember correctly, iTerm2 has been on GitLab since before the acquisition.
How come it says that it's mirrored from GitHub and "The repository failed to update 8 months ago. Repository mirroring has been paused due to too many failed attempts, and can be resumed by a project master."
Seems like they are still using GitHub but use GitLab for the wiki?
They use GitLab for the issues I think.
Github’s issue tracker is lousy so issues have been on gitlab since google code slipped this mortal coil. I don’t want to lose my GitHub stars so code remains there. I guess there’s not much reason to change it now even if github does improve.