How to register an account on GitLab. Due to spam, new accounts are locked until approved by an admin or the approver bot. Your GitLab account gets automatically approved within one hour if you are a member of Trusted Contributors in Gerrit, or a member of the Trusted-Contributors group in Phabricator and linked your Developer account to your Phabricator account. If none of these apply, you can file an unlock request to expedite access.
Support: mw:GitLab, how to host a project on GitLab, #wikimedia-gitlab on libera.chat, #GitLab on Phabricator.
And make sure it's writable for everyone, which seems to be equivalent to what MediaWiki does?!
This can be reproduced by creating a wiki (via install) and then immediately running integration tests on it. This will fail like:
fopen(/var/www/html/w/cache/docker/wikidatawiki/mw-GlobalIdGenerator1000-UUID-128): Failed to open stream: No such file or directory