gitea: Opening empty repository -> error 500

• Gitea version (or commit ref): 1.9.1
• Git version:
• Operating system:
• Database (use [x]):
  • PostgreSQL
  • MySQL
  • MSSQL
  • SQLite
• Can you reproduce the bug at https://try.gitea.io:
  • Yes (provide example URL)
  • No
  • Not relevant
• Log gist: 2019/08/19 16:18:03 …ules/context/repo.go:594:func1() [E] GetBranches: No branches in non-empty repository /gitea-repositories/xxxxxxxx/xxxxxxxxxxx 2019/08/19 16:18:03 …s/context/context.go:137:HTML() [D] Template: status/500

Description

I did an update from 1.7.4 to 1.8.3 and 1.9.1 and in some repositories I get a 500 error files exist along the path gitea-repositories How to restore repositories?

Screenshots