Created attachment 109773 [details]
Error

Mouse pointer have lag.

Mouse pointer behaves as if it has an invisible square attached to it. This square covers some area next to the pointer, but it is not always clear exactly where (a link to a screenshot is shown below, please note the white square with some text from the previous webpage displayed in that window).

This makes selecting text difficult, as one never knows where exactly the selection ends. Also, scrolling in some windows becomes problematic, as the pointer shadows a part of the scrollbar. When a text is being typed, one needs to make sure that the pointer is parked sufficiently far from the text (so, to make a long story short, this is very annoying).

(A link to the screenshot: https://goo.gl/photos/92KKGyFs3AkdxYb79)

This happen with driver propietary of Nvidia Optimus. This have workround restart sddm after login.