That certainly installed DLM, and crashed the PC. I rebooted and did as you said, the service failed to start because it is masked.
Code:
# systemctl start displaylink.service
Failed to start displaylink.service: Unit displaylink.service is masked.
Edit: kicked off:
Code:
# systemctl -a
UNIT LOAD ACTIVE SUB DESCRIPTION
● display-manager.service not-found inactive dead display-manager.service