Problem with root_url


I tried to configure OAUTH for my drone and after doing so I wanted to authenticate it.
Instead of refering to https://xxx/gitea/login/oauth/grant I was to referred to https://xxx/login/oauth/grant.

I configured the reverse proxy for nginx according to the documentation.
I am currently using gitea 1.9.3.

I solved it by buying my own domain and creating sub-domains for my services. This problem does not occur any longer with the current setup.