Hello,
If you are using DisplayLink Manager v1.x with Catalina or Big Sur then unfortunately Clamshell mode is not going to work with those. It is its current limitation that we are working with the OS vendor on.
For Catalina you can downgrade the driver to our legacy drivers like 5.2.5.
We do not have any workarounds for Big Sur other than keeping the laptop lid open as of yet.
More information as well as how to revert to a previous versions of the DisplayLink drivers can be found here:
https://support.displaylink.com/know...ntroduction-in
Download link for legacy driver 5.2.5 is available under the following link
https://www.displaylink.com/downloads/file?id=1636
Best regards,
Katarzyna