The 'Delete' keyboard key doesn't always work in the main panel.
Steps to reproduce:
Have Track Details in the main panel and tag editor docked at the bottom.
Select a range of tracks by clicking while holding [Shift].
When you press [Del], you are not presented with the option to delete those tracks. (Because the focus went to 'Track title' in the Tag Editor panel.)
And some other behaviour in the Track details panel I wouldn't expect:
When you select a track there, and then use the [Page Dn] key, focus is lost on the track that was selected before, and a whole different track gets selected.
I would expect the selected track to remain selected.