I also observe problems with a flickering mouse and a weird rectaangle around my mouse, when I use three monitors, with one beeing rotated by 90 degrees. Sometimes this also occurs when I don't rotate the screen. The fix above doesn't help me.
Ubuntu 17.10, Display link driver 4.1 and Nvidia 390 open source driver
GPU: NVIDIA GT640M
I also observe problems with a flickering mouse and a weird rectaangle around my mouse, when I use three monitors, with one beeing rotated by 90 degrees. Sometimes this also occurs when I don't rotate the screen. The fix above doesn't help me.
Ubuntu 17.10, Display link driver 4.1 and Nvidia 390 open source driver
GPU: NVIDIA GT640M