Comment 4 for bug 1689356

To be able to use the UI of both Ubuntu and any applications you're using when running Ubuntu in a high resolution mode you have to use the UI scale settings. With the scale settings resetting every time the display sleeps a high resolution setting becomes practically useless.

As this issue has the impact that high resolution settings become useless it should be prioritized, especially since there are no workarounds available as far as I know.