Installing macOS 10.13.4 will cause DisplayLink connected displays to go blank after the OS update when using DisplayLink driver v4.1. Extended displays continue to work as expected in macOS 10.13.3, and we can only recommend that you stay on macOS 10.13.3 or earlier if you require this feature and have not already updated. Functionality such as Ethernet and audio, where implemented, is unaffected.
We released DisplayLink driver v4.3 beta 5 providing an interim solution with one extended USB display (720p or 1080p) on macOS 10.13.4, using Apple AirPlay®. All additional DisplayLink screens will be cloning the primary display. Please see the simplified FAQ for details on how to enable Apple AirPlay with DisplayLink display for extend or mirror mode.
Our team has made some solid progress towards finding a solution which would restore full extended display support for multiple DisplayLink displays in a future release of macOS, but we are unable to provide a time-frame or a date for release of this solution at this time.
* What's the difference between clone and mirror?
With mirror, the screen is part of the user-controllable display settings and the user can choose which screen to use as the source. This affects resolutions and aspect ratio chosen for mirroring.With clone the source is always the current main screen resolution and no display controls are available to the user. The DisplayLink screens will scale and/or letterbox as necessary.