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another case: an IT admin is remotely accessing her personal workstation at the office and is reading sensitive material such as passwords or other documentation. Any passers-by could see this and take a picture with their phone. Is the only option to turn on blanking for all (or none) Guest Sessions? Blanking all sessions would greatly disrupt our help desk techs who need to work with users directly without blanking their monitors/input.

"Join with Options" already contains a checkbox to "suspend my input". Seems like it would be fairly trivial to add "Blank Guest Monitor" and "Always Blank Guest Monitor as join options if not being able to create an options group of some sort where machines would take on this designation by default. Seems like it should also be the default for servers but I believe is being addressed in another topic.