Describe your idea for an enhancement:

If I use ProxyAuth to service-a.mydomain.com, I get redirected to voidauth.mydomain.com to authenticate.
So far so good.
But after the authentication I am 'just' logged in voidauth.mydomain.com. I need to go to service-a.mydomain.com manually.
I expect to re-redirect back to the initial service-a after the successful authentication.

Additional context:

Try to copy the behaviour from authelia?