Can't select Backup Location — Project Save and Load

In System Preferences >User>Project Save and Load, under 'Save Settings' I can't change the Backup Location.

I can browse to a Folder on my Mac, but it inputs a wrong file path (repeating the folder name several times) and the folder is not selected after a reboot.

Sometimes I can't even click the 'Browse' button, and sometimes the button shows a non-Mac style Finder window.

Mac Pro 2019 - Sequoia 15.4.1
20 beta 3