After Hirsute Hippo rebuild --mouse cursor = 16 horizontal lines?

et al:

Yesterday was Hirsute Lubuntu morning, for the second time when I’ve booted it up and saw there was a smallish group of horizontal lines in an amorphic cloud on the display ??? Logging into the GUI and the cloud was still there?? Oh, that’s the mouse cursor?? How to use this “cloud of lines” to mouse around? Logged out and back in, cloud of lines was still there.

The previous time this happened I rebooted into 5.11 recovery and ran dpkg and rebooted back and the regular cursor was again there. After that I ran an apt dist-upgrade, pulled in “204 packages” . . . rebooted and again the 16 horizontal lines of amorphic cloud style cursor returned.

Yesterday, the cloud of lines was there on log in, I checked “mouse” in preferences and selected the “white option” because I have “dark theme” . . . there were some updates in apt, on reboot . . . cursor cloud of 16 lines remained. Did not again try recovery since the problem returned after running an update the first time and still was there after second apt dist-upgrade.