I have a self-managed GitLab CE v13.1.3 on CentOS7 (omnibus installation).
With the last update (the previous version was 13.0.4) “New Project” button disappeared from the Groups pages (all).
Only from Admin Area, “New Project” button is available, but selecting any group (also a new group) as namespace, the New Project Creation fails with the error “The form contains the following error: Namespace is not valid”.
I tried also to transfer a project to another group, but it failed too.
From GitLab logs no useful information I fetched
Any ideas or suggestions?