I doubt there was a problem cloning GitLab-hosted repos on CircleCI before this announcement. But there are plenty of non-Git things that these hosts do; pull

I doubt there was a problem cloning GitLab-hosted repos on CircleCI before this announcement. But there are plenty of non-Git things that these hosts do; pull requests, status checks, etc. I am guessing that "support for ..." entails all of those extras.