I think the selector for the Launcher in many modals/pop-ups (Add alert, Add to collection, etc) is the main option everybody use when adding games to alerts or collection so it should have a better UX/UI than just a list.
As it is currently, you have to scroll when you open this filter to see all options, and half of the space of the list is just blank unused space.
You could improve it placing launchers/stores in a grid-like way. This way, the space that currently is used by 2 launchers/store would fit 3 launchers/stores, and would give a better UX to click on. And less or even no scroll needed.
This is just a 5-minute CSS crafting to mockup what I mean:
What do you think of this?