We all know that desktop KVM is generally an unreliable technology, but it's more reliable than most. I have a 2017 Macbook Pro, a Windows 10 desktop, a 27" Dell 4k monitor and various peripherals. In general, I can successfully switch back and forth. Macbooks sometimes have trouble feeding video to a Dell monitor, but I think it's a displayport issue in recent versions of OSX and I was able to get it working mainly by updating the displayport driver (if you're having trouble with the laptop trying this). Switch to dual displays but the display stays idle, google "os x displayport driver update". I bought this to replace another Siig KVM that I found mostly unusable. Maybe it's just a comparison, but I'm very happy with it.
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