This is no longer an issue with macOS 10.14 Mojave onwards, and DisplayLink recommends updating to Mojave to solve this issue.
Users on High Sierra 10.13.4-10.13.6 who cannot update to 10.14, should install v4.3.1 for one extended USB display with multiple resolutions through an additional menu via Apple AirPlay.
An FAQ details how to enable Apple AirPlay with DisplayLink display for extend or mirror mode.
DisplayLink driver v4.3.1 is applicable to Mac OS X 10.12 and macOS 10.13.
Driver v4.3.1: http://www.displaylink.com/downloads/file?id=1251