There are themes with Aero, and themes that don't have Aero; I was using Windows Classic, which isn't an Aero theme, and apparently the lack of Aero is what causes screen tearing... even though I didn't have the problem up until recently, so go fig.
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Christmas Music
Macy's Thanksgiving Parade
Sesame Street debuts on Netflix
Back to the Rock Season 2
Sam and Friends Book
Jim Henson Idea Man
Bear arrives on Disney+