When I close my laptop lid and reopen, I'm faced with my login greeter (lightdm-webkit2-greeter) and the mouse cursor appears just fine. When I enter the credentials and initiate the actual session (i.e., get to the desktop), the mouse cursor becomes invisible.
I can still hover over things and click on them, but the cursor is invisible. In my case I can only get my cursor visible again when I reboot the system (or hibernate and come back from it).
This is a clear regression since I upgraded to GNOME 3.20 from the latest version prior to that. I'm not clear what the number of the version was, but I'm positive it was the latest, since I update my computer on a daily basis.
According to other reports, downgrading to xorg-server-1.18.1-3-x86_64 solves this issue, and updating it to the current version (xorg-server-1.18.2-4-x86_64) causes the bug to reappear, although I can't confirm it. Source: https://bugs.archlinux.org/task/48713
Assuming you're using the intel driver, this is a duplicate of bug 94677.
You're probably right, as I use the Intel driver.
*** This bug has been marked as a duplicate of bug 94677 ***