[Trisquel-users] Re : Using old iMac as display for newer macbook?

[lcerf]

Trisquel 8, with the MATE desktop environment by default, has Vinagre  
installed by default (it is probably called something like "Remote Desktop  
Viewer" in the main menu): https://wiki.gnome.org/Apps/Vinagre/

Go for VNC: you do not need the SSH's encryption (with a performance cost)  
because you will not leave your local network.