First release, tested on Fedora 36/37 with Gnome 43 and Windows 10/11.
For Linux make sure to chmod + x PyPassManager-Linux to allow the program to execute
On Windows the application may not be able to create the required "data" directory for placing database files right from your Downloads folder. Try creating a folder somewhere (like 'documents') and place the file there.
Some known issues: Attempting to register an already registered account doesn't throw an error, window placements can be erratic on Windows (should be fixed now.)