Just upgraded to 11, and it appears to be fixed for me! This was my simple repro case in version 10, which now doesn't repro in 11:
My simple test is to just click and drag in the desktop of the VM. That produces a dotted rectangle showing the selection area as you drag. If I initially click or drag into the top 40 pixels of the screen, that's when I see the mouse problem, as the drag rectangle goes away and selects whatever was in the rectangle at that point, as if I had released the mouse, but then it starts a new drag rectangle at the new location. It only happens if I click/drag into that top 40 pixels. I doesn't happen in VMware with an identical test.