Sorry to hear you are having trouble.
My mouse cursor on my primary computer gradually starts to disappear when I run multiplicity. I have only one solution: when I have visited my second computer and use my primary again, I exit multiplicity as soon as I am able to do before my mouse cursor starts to disappear so much that my primary computer becomes unusable. If I wait too long, then I have to reboot my primary!
While very rare, I have not seen it 'gradually' disappear, unless you mean 'over time' it is gone.
A reboot is not needed but the two solutions are not all that much more appealing...
-On the primary (Win10):
- Ctrl + Esc
- Type 'mouse'
- Tab to 'additional mouse settings'
- Ctrl + Tab to 'Pointers'
- Change the 'Scheme' to something else with up/down arrows
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