Hello! I will state right off the bat that I understand that Plugable does not officially support their products’ usage on Macs. Nonetheless, I appreciate you taking the time to read this.
I have a Macbook Pro and two HP LV2311 monitors, all connected to the 3900. The two external monitors basically mirror each other. I am running Catalina, and when I open up Display in System Settings, this is what I see:
The two screens that show up are both the HP monitors. Ultimately, I would like the laptop monitor and the two external monitors to be extended displays. Hopefully this is a decent explanation. Let me know if you need more information from me. Thanks for your time!
Thank you as well for the detail you have provided that is much appreciated.
As you mention, we do not support the use of the UD-3900 on the Mac platform (we have not supported the UD-3900 on the Mac platform since the release of Mac OS X 10.9 in 2013 due to performance issues within the operating system) however we will of course do our best to try and help point you in the right direction.
Based on information in those threads, it would appear that uninstalling the current ‘classic’ or ‘legacy’ DisplayLink driver for Mac and then installing the new ‘DisplayLink Manager App’ application has helped others with a similar problem.
** Please note - one of the current limitations with the new DisplayLink Manager App is that ‘Closed-display mode’ (also known as clamshell mode) is not possible. This means that the laptop lid must be open and the laptop’s internal display be active in order to use the dock.
I know you mention that the final result you wish to achieve is to have use of all three displays (the laptop’s internal and the two external connected to the dock) so this limitation will not be relevant in this specific case, however I wanted to make mention for the benefit of any others following this forum thread **