Okay, I've tested with both Codex and Claude, neither of them work despite both saying (in Safari) that connection successful, and you can close the window.

@DTS Engineer Hi! Yep, here: FB23066171

Hi, Albert. Despite many attempts of trying to sign in that way, even though the pop-up window tells me I am logged in and can safely close it, nothing changes in Xcode and I am still shown as if I'm logged out.

I tried this but unfortunately I'm still getting the Not Signed In state in Intelligence > Codex on the Account row.