Document how to redirect to user's target URL on authentication

[arribatec-cloud-1]

Sometimes the user is logged out in the middle of using the app. This will prompt user to log back in, however when the login is finished, the user is taken to a static "landing page" instead of going back to what she was doing.

There is no example in the documentation on how to redirect the user on her way after authenticating in this case.

[tomasvotava]

In most cases this is done using the state parameter, I will add an example with this, thanks for the tip!