P.S. In the PureOS store on the L5, if you click on an installed app, it will open its page, where you can check what kind of package it is: flatpak or native PureOS app.
[EDIT: That’s also where the trashcan button (for uninstall) is found, if you prefer to uninstall that way.]
For months I have not used the app PureOS Store, I only use sudo apt ... The app PureOS Store seems to be buggy. It never end the spinning wheel when I search for something, also not when the app for which I do a search is already installed. Is it save to delete it?