Re-tapping on Folder icon in Data Manager doesn't offer "previous selection or all tracks"
Re-tapping on Folder icon just toggles visibility of all tracks in folder at once, instead of offering "previous selection or all tracks", as described in manual:
Tapping it visualizes all tracks in the folder on the map. Re-tapping hides them all. If you previously displayed only some tracks from the folder, tapping offers to display your previous selection or all tracks.
Locus Map Pro 3.31.3