I have this too, since beta.
One simple workaround would be, to leave left panel by pressing '1' instead of 'Shift' (or whatever binds to "Toggle UI Focus").
If you have a HOTAS, I recommend assigning a button on the throttle to 'Switch to Left Panel'.
If you switch that button to 'Hold' instead of 'Toggle' you save one button-press for quick things like checking contacts or requesting to dock.
Or, you could use something like TrackIR, FreeTrack, OpenTrack or Oculus Rift and save the keypresses altogether...

(I wish I could do that)