DisplayLink Mac OS X Software - User Guide
Setting the Display to Mirror mode
When in Mirror mode, additional displays will display what is being shown on the primary display. Checking the “Mirror Display” on the ‘Arrangement’ pane enables this feature.
Display Preferences:
Displays set to Mirror
Setting the Display to Extend
To extend connected displays, make sure that the “Mirror Display” on the ‘Arrangement’ pane is unchecked.
Display Preferences:
Display set to Extend
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