I'm stuck in this part to finalize the project. The theory is this, you logged into client.site.com, and you access site.com and your login data remain active, without having to log in to site.com.
I had asked the same question here, I put all the code I'm currently using it, but I did not get the answer if there's a way to get that user return logged in on site.com and how.
Resolved in the original question: