Just my observation of macOS Mojave 10.14.6 and the installation of DisplayLink 5.2. Mojave 10.14.6 is just been made available yesterday. DisplayLink 5.2 has been available since early July.
I had previously installed DisplayLink 5.2 onto a Macbook running macOS Mojave 10.14.5. For this testing, I had 2 cases: 1) I installed DisplayLink before the Kernel Extension was allowed. 2) I installed DisplayLink after the Kernel Extension was allowed.
In both these scenarios, DisplayLink still worked as long as Kernel Extension has been applied.
But for macOS Mojave 10.14.6, If I was to install DisplayLink 5.2 before Kernel Extension was allowed. Then external monitors don't work.
If I was to apply Kernel Extension first, then install DisplayLink 5.2, then it is fine again.
This feels stupid to me, because if the wrong sequence of installation happen, then we have to run the DisplayLink uninstaller (restart required), and the reinstall DisplayLink 5.2 (another restart).
Anyone else experience this for their Mojave 10.14.6?
I discovered the same. On my 2012 MacBook Pro (tried connection via Mini Display Port to Display Port and HDMI to HDMI) the external monitor(s) is not working.
But my iMac and my 2017 MacBook Pro work still fine with an external monitor. (Connected via USB-C/HDMI Adaptor to HDMI and HP-USB-C Hub Display Port to Display Port.)
I have booted my MacBook pro also from an external disc with Mojave on it. And it still doent work.
I will let you know if uninstalling DisplayLink 5.2 would resolve the problem.
Update: no, i didn't. Next step would be to reinstall the system. But i start to assume that there is a hardware problem. If I connect my MacBook Pro 2012 with Mini Display Port to Display Port cable, I get the external screen having this picture:
@rda0007 if it's any help we are using Targus 4k hubs and they work, USB-C from Mac to hub, monitors are HDMI or display port and can be mixed, e.g. 1 on HDMI 1 on DP, ethernet, USB-A and USB-C ports on the hub all work.