Feature request: Redirect from `/welcome`

Is your feature request related to a problem? Please describe. A blank page when accessing /welcome.

Describe the solution you'd like

1. I suggest redirecting an end user to 404 page or somewhere else so he does not see a blank page when accessing /welcome as the page is not intended for him. This the 1st case.
2. The 2nd one is when a developer did not set GitHub authentication[^1]. I also suggest redirecting so an end user does not see instructions how to do it as it does not make sense for him.

[^1]: did not provide environment variables