Solved!
@jmarkows said in Pop-out Panel Power Problem:
I don't have any solutions other than it's not a universal problem.
That in itself is important information too, because it meant that the solution was to be found on my PC, and not a problem for Black Square to correct.
I uninstalled MSFS and reinstalled a fresh copy of it. That did nothing.
I then moved the Packages folder from my system drive to a second drive. No joy.
Then I noticed that the controller profile for my Honeycomb Bravo was not empty. I use Spad.neXt to control all functions of the Bravo, and the associated profile in MSFS should be empty. Why didn't I check that first?
I deleted all bindings that were there, except two for the battery and alternator, which were bound to one of the rocker switches of the Bravo. With those two bindings in place the problem persisted. When I deleted those two last remaining bindings I had no more unwanted power switching. Succes!
Apparently MSFS not just sends events when I throw a switch on the Bravo. All events associated with a controller are sent also when the mouse pointer leaves a popped out window, in my case triggering unwanted switching of the electric circuits.
@jmarkows Thanks again for your help!