Is it possible to add a redirect to Forward Auth so that it will redirect the request after successfull authentication

[minozheros]

I tried to use forward auth with an application that has inbuilt authentication. So I set up the SSO within the application, and it is working properly. I would like to use forward auth though, because I don't want people to be able to reach the application at all if they are not authenticated.
I managed to set up forward auth, and it does work, but it only redirects to the main URL, which means I always have to authenticate again with the actual app, which doesn't seem to be desirable. I am wondering if I can redirect the request after the authentication to the proper sso link of the application, so that it would login automatically as the auth process already happened and the needed token is present.

I am not sure if this should be something that the authentication provider facilitates, or if it would be better for the app to check for the token and allow users to pass. As long as not every app automatically checks for a valid token it would be nice to be able to redirect requests after the forward auth has been successful to the address where the app will kick off the internal sso process.