Same problem here. Catalina installed without a hitch but my Logitech problem is a bit subtler.Mac mini late 2012, Logitech wireless keyboard 800 (Unifying receiver, not Bluetooth)Background (in case any Logitech engineers/experts are out there):I completely uninstalled all Logitech software, preference panes, and the like. Apparently several versions were present and some dated back to 2015 or so.Then reinstalled what appears to be the most recent Logitech drivers for Mac: "Logicool". I say 'appears' because it is the only download that lists 10.15 as an available Mac OS version. And the "Logitech firmware update" which recognized the Unifying receiver and reported a successful firmware update.There are probably 12 or so available Logitech downloads and it's not clear which ones are needed to get a specific piece of hardware functioning.Then verified that both the Logitech Control Center Deamon and the Logicool Unifying Software were enabled in the "Input Monitoring" panel of the "Privacy" tab of the "Security & Privacy" System Preference Pane.After updating the firmware on the Unifying receiver, it's possible to pair the keyboard using the "Advanced" option in the Unifying software.Note that the Unifying software only recognizes the keyboard using the "Advanced" option. The usual workflow of cycling the power switch gets you nowhere.Using the "Advanced" option....the keyboard is recognized (state goes from inactive to active when you pound on the keys), yet no characters appear either in the Unifying test box or anywhere in the computer itself.