I have a MacBook Pro which I use to connect to my iMac, using Target Display Mode (TDM) via Thunderbolt.
Furthermore, I've got a secondary screen connected to my iMac via an DVI cable.
When I invoke TDM, my MacBook will take control of its own screen and the iMac screen.
But the 2nd screen is still displaying my iMac.
What I would like to do here, is continue to use my iMac, only on the 2nd screen, while the MacBook gets to control my iMac screen.
The mouse of the iMac still works on my 2nd screen. But the iMac keyboard does not work. For some reason, the only character I can type with it is a.
Question: Is there a way to get the iMac keyboard working in this setup?
This is kind of what my setup looks like (not my image, but pretend it’s a MacBook Pro, iMac and secondary screen):