Mouse Scroll Wheel does not work on Side Pannels

Mouse Scroll Wheel does not work on Lighroom side pannels.

For as long as I can remember, my mouse scroll wheel will not work on the side pannels of Lightroom Desktop (v6.5).  Works fine in the main window grid and works fine in Lightroom Classic (all pannels), just not on the left or right side pannels of Lighroom on desktop.  The only way to scroll on the side pannels is to use the impossible small scroll bars that automatically hide when not in use.   This creates a disruptive workflow.   

Update - Actually, it sometimes works.   When I "click" on a catalog, sometimes, only sometimes, the control shifts from the main window to the left side window, at that point, I can scroll.   This is a flacky issue, however, only sometimes does the focus change from the main window to the side window, I can not realy on it happening.  

Am I missing something?