For anyone else who is going bonkers on this one and finds this thread, following the youtrack trail led me to the fix:
"apparently the behavior on Windows 10 can be turned off.
On Windows 10, left click at bottom left corner, go to Settings->Devices->Mouse & touchpad, and turn off “Scroll inactive windows when I hover over them”. Selection menu wheel scrolling should work like it used to."
Worked for me and restores at least some of my sanity, thanks guys.