After upgrading to Pods 3.0.0 on WordPress 6.3.1 (PHP 8.0), I can no longer save Custom Settings Pages with relationship fields (related pages). I’ve verified the issue by installing a fresh WordPress 6.3.1 site with only Pods 3.0.0 running.
When trying to save the Custom Settings Page, the spinner just keeps spinning and the following console error shows up: Uncaught ReferenceError: STORE_KEY_DFV is not defined.