Magnifier tracking settings
Irrelevant. I'm not interested in disabling mouse tracking. I only have mouse tracking enabled. All other options are disabled.
Keep the mouse pointer
I can't reproduce this when it's set to "Within the edges of the screen", but this is an annoying mode for me to work with.
But this does mean we might consider this is an issue with the "Centered on the screen" option.
As soon as I moved back to "Centered on screen", I tried the Windows + Shift + S trick again and it worked second try (meaning the cursor position is off again).
Switch Magnifier view mode
Irrelevant. I'm NOT going to work in docked or lens mode. I assume the issue won't be reproduceable in these modes.
Reduce zoom to a lower level where possible
Seriously? Great idea, now I cna seee waht I'm tping!
Avoid rapidly moving the pointer while Magnifier is starting
Great workaround, not a solution though.