I don't recall downloading anything on to it recently, but I haven't done forensics yet. As if I didn't have enough things to do...

Thanks.

Cheers,
Scott.
("But I thought Winders Defender was supposed to be a great AV program!!!1")

No change.

Decided to delete all my Chrome Extensions except for TamperMonkey and UBlock Origin. That finally worked. Apparently one of the Extensions had been infected. Deleting all the others (an HP35 calculator, a font extension, an "Edit Office files with Google Docs, an HTML5 video autoplay stopper, and a couple of other similar things) got rid of the offending behavior.

Hope this helps someone else out there.

Cheers,
Scott.