Here is what my current OAuth2 Authorization looks like when I click configure on authentication while configuring the remote mailbox.

Here is how it has looked in the past (there is a token tab).

The highlighting is due to this image being from previous documentation we were using.
This disappeared after I upgraded from PHP 8.2 -> 8.4.6
To my knowledge 8.4.x is supported by osTicket 18.2 so I believed it would go quite smoothly.
Subsequently osTicket is not collecting responses from email replies so I believe these issues are related.
Any thoughts or help is greatly appreciated I could be completely out of my depth here.
Oath Plugin Version: 0.6