In other words, there's a number of issues assigned to me listed there, even though they're closed. There's also a few mentions that I don't otherwise interact with (I've seen them in my email and that's that), so I'd have to manually mark those as Done in the GitLab interface after reading them in my email.
Well, that's not flawless. I never use the TODOs view, because it's full of items like this:
https://screenshots.firefox.com/wxy2llOZM5g0HWre/gitlab.com
In other words, there's a number of issues assigned to me listed there, even though they're closed. There's also a few mentions that I don't otherwise interact with (I've seen them in my email and that's that), so I'd have to manually mark those as Done in the GitLab interface after reading them in my email.