If there is no rotate option available for displays connected through a dock, check that DisplayLink software is installed.
If the DisplayLink Manager is installed do the rotation through that instead of using the System Preferences: Displays rotate option (which is not available). If this fails, check the DisplayLink software is fully up to date.
My latest blog post: A Different View: People whose ideas differ aren't bad, they just have a different view. (posted 2025-07-22). Warning: mysqli_connect(): (HY000/1040): Too many connections in /Library/WebServer/Documents/Owen2/Inc/Footer.m.inc.php on line 51
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