Multiple Select - Three panels
 

In the Music Playlist, and the Clock & Logo panels there are multiple list items. In the Fish Sets panel there are multiple fish sets.

"Multiple Select" should be possible, so that "Remove" (or Delete) can be done more easily.

It's not a really big deal, but it's "how Windows applications are supposed to work".

I looked into it early on. It's too difficult and causes too many problems.