Use a iMac late 2009 27 as external display for new MacBook Pro
I have a new 2019 MacBook Pro 15”. I would like to use my old 27” iMac (late 2009) as an external display. What do I have to do? I’ve found instructions for using a mini DisplayPort out to the iMac, but the new MacBook Pro doesn’t have that. Thx.
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