Improve the visual separation between the lines of each app
I'm worried about having too little visual separation between the different lines of each app and the buttons on the top-right corner of each app.
I think that some people will confuse the buttons of each app, eg. click on [Install] for OpenRefine to install KeePassXC, especially further down the list.
We should add some more visual clue to delimit the lines of each app.
For example, a Gtk3 vertical lists like suggested in #69 would solve this: