Apple has released the final version of macOS Catalina 10.15.5. I downloaded and installed the Combo Updater. It took quite a while to install. After booting into the install I did another Restart. I have been using it for a while and all seems well. The Finder is behaving properly and the update seems to be very responsive. I have not yet found any App that does not work with it, but YMMV. This article covers what has been updated and fixed, check it out. I am assuming there will be a 10.15.6 update to Catalina, but we will have to wait and see.