It’s a hard wired mouse. Of course, I couldn’t finish the bounty. The cursor was still moving around the screen, I just couldn’t see it. 16" MacBook Pro, latest OS.
This has happened to me when I was running D3 on High Sierra on an Intel Mac some years ago. If I remember correctly, I just command-tabbed out to the Finder and back to D3 and it was there. Was running in windowed fullscreen with a wireless Magic Mouse 2.
I’ve since moved to an M1 iMac running the latest OS as well (Monterey 12.2.1). Although, I use the wireless Magic Mouse that came with the computer and have had no issues with it (iMac came with Big Sur -I think 11.4 - and I had no issues with the wireless mouse as well).
Though it’s happened to both of us (wired and wireless mice), it might help to check if the mouse drivers are up to date (if even necessary) as there could be conflicting/corrupt files with your mouse that is causing this to happen.
Hope this helps/fixes/gives more insight on to what a solution could be for you.
Let me know how it goes 
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This has happened to me, but not in game. The reason was related to low memory space.
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