Can't move areas any more!

I just fired up photoshop and discovered if I select an area on a background layer and try to move it, or move + copy it, the cursor moves, but nothing else does. there's no UI to indicate the area is being moved. releasing the drag does drop it in the new location, but it's impossible to drop it accurately. same with Rectangle objects.

if I try to move a layer with the Move tool, or with the Control key pressed, it doesn't move at all. (update: now it does, but invisibly, like above; so...flaky?)

this is particularly weird since I just went through a lot of hassle trying to solve a similar Illustrator problem, where I wasn't able to move elements except using arrow keys or the element's center point. I ruled out preferences being the issue. I ended up updating all the non-Illustrator Adobe products, and Windows, all at once, and it seemed to resolve the issue.

Photoshop v20.0.1, Windows 10 Pro 1803. 256 GB RAM.

the layer's definitely not locked. i've tried unchecking "use graphics processor" and relaunching.

is there a shared resource that could be responsible for these issues? now that everything's updated, i'm not sure what to try.