When I startup Xubuntu 18.04 beta on my 4K TV (connected by HDMI) the cursor is much too big. The system will boot into Full HD resolution and not 4K. If I then go to the Xfce Mouse settings under the tab "mouse themes" to change the cursor size I only need to change the size of the cursor 1 pixel up and down and everything is fine again and the cursor has again the correct size. In my case I change the cursor size from 24 to 25 and then back to 24.
When I startup Xubuntu 18.04 beta on my 4K TV (connected by HDMI) the cursor is much too big. The system will boot into Full HD resolution and not 4K. If I then go to the Xfce Mouse settings under the tab "mouse themes" to change the cursor size I only need to change the size of the cursor 1 pixel up and down and everything is fine again and the cursor has again the correct size. In my case I change the cursor size from 24 to 25 and then back to 24.