[jesperhh]

This is likely because the gpu has specific hardware for drawing the cursor on top of the current framebuffer, which can be turned off quicker than the character can be drawn to the framebuffer

[swinglock]

Indeed it does. When using f.lux the color temperature of the cursor remains unchanged due to this.

[kevingadd]

You can also observe it in many cases while dragging a window - the composited window's position will lag behind the position of the cursor.