Mouse clicks stop registering in some or all windows
Solution 1:
Well, it's been several days since I removed a short USB cable extension I had connected from the computer's USB-2 port to the cable from the old passive USB hub, and through several reboots and suspends, I've had no more problems
I hope this might be helpful for others, as I've seen a bunch of very similar, or even duplicate, situations both here and elsewhere. Mostly, they were older topics, and although I tried posting to get more information, I got no response.
I'm tempted to wait a while longer before accepting this as the final solution, but I'm afraid I'll forget, so I'll close it now.