Enable public read only access to wiki of private repository

We want to give WIKI read access to consumers of our json-apis and keep rest of the repository (all of it - including issues) private. Simply put we want to have public documentation page.

This was requested many times, from issues I understand some work was done, but I cannot get it configured correctly.

I tried different combinations in Settings | Visibility, project features, permissions, i also tried to change Project visibility from private to internal, but could not get public wiki access, also tried with dummy-user. When dummy-user is not part of project (wiki set to “everyone with access”) , nothing is accessible. When dummy-user is guest to the project, he can see issues, pipelines, analytics, members (non of this is wanted). He can see wiki menu, but it’s empty.

I cannot find any combination to get desired result. It seems simple so do I miss something or is it still impossible?