I think this is a new one, and it probably should be pretty easy to do, too:

I like to modify info on single tracks while I play, so I leave "protect library" unchecked. More than once I've tried the move the bar to scroll through crates, but instead accidently moved a crate where it became a subcrate somewhere it didn't belong. I'd like to be able to lock my crates & subcrates, yet still be able to edit track info.