Use case or problem
Hiding sidebar which contains file-explorer, search, starred, … requires effort or it takes valuable space when working on small screen.
when left sidebar is not pinned: automatically hide left sidebar and when clicking outside or pressing escape. Just like some menu in other programs, e.g. top menu in PDF Foxit Reader.
Show it again e.g. when pressing hotkey for global search. Keep current behavior when it is pinned.
Current workaround (optional)
Move mouse to corresponding icon to hide the left sidebar, or use corresponding keyboard shortcut.