Reported by @pulsar moth
Try to do something in ChatGPT agent that requires taking control of the browser for a login event with Apple.
In my specific case, trying to "Sign in with Apple" under the Atlassian signin page. You can click the button at id.atlassian.com/login, and compare it to the other "Sign in with" methods on that page.
I think that this issue holds in general; I've just tried it on slack.com/signin, with the same issue after trying to sign in with Apple.
I should be directed to apple's signin page, where I can enter my credentials/passkey, and then be redirected back to Atlassian, or whichever service that I was originally signing into.
I'm lead to a blank page; the actual page never loads. This seems to be a networking issue from within OpenAI's environment.
ChatGPT Agent's Chromium Browser