[REG: 5.10.1->5.11.0]: When doing something that would require quick updating, the updates can lag behind the requests. This was introduced by 0f6a6b2bffb9b9d0a5db8b9473fda108d14e9915 in qtbase.

In the example attached, click on the circle and move it around and you will see it is slow to react, whereas in Qt 5.10 it will update without a problem.