DisplayLink is warning of significant macOS issues as shown here. This is the official word from DisplayLink.
The issue is not limited to Targus Universal Docking Stations, or even DisplayLink based docking stations, but it is associated with competing USB graphics solutions as well. i.e. https://en.j5create.com/pages/drivers .
Targus continues to communicate with DisplayLink, and others, regarding any possible work arounds or status that Apple may share. The moment we have any information that we can share, it will appear on TargusBlog.com, please “Follow” the blog if you are not already.
Thee DocKtor also recommends that macOS users request support from Apple for these issues, and so that they have full awareness of the issue(s) you are experiencing.
Some functionality is available with the DisplayLink USB Graphics Software for OS X and macOS 4.3 beta release. However, Thee DocKtor has not validated this release for use on Targus Universal Docking Stations with any version of the macOS or OS X.
Thee DocKtor is recommending that macOS users stay on macOS version 10.13.3 and use DisplayLink release 4.1 until Apple releases an update to fix these issues.
Status at DisplayLink as of July 29th, 2018
Installing macOS 10.13.4 or later 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 below. Functionality such as Ethernet and audio, where implemented, is unaffected.
Meanwhile, we have a workaround solution which enables one extended USB display (up to 1080p) on macOS 10.13.4 and later, using AirPlay. This is available in 4.3 beta. If you require multiple DisplayLink screens in mirror or extend mode, we recommend that you stay on macOS 10.13.3 or earlier at this time.