Sharing GUI windows between Macs
Solution 1:
Well, if you start an Application that uses X11, just like that : ssh -X user@host
You can run most "Linux GUI" X11 applications on mac as described here using docker: How to run a Linux GUI application on OSX using Docker
Make sure to check out XPRA for Mac, too. You can forward X11 apps on mac or forward the whole mac desktop using xpra, to install do
brew install Caskroom/cask/xpra
to shadow the desktop
/Applications/Xpra.app/Contents/Xpra_NoDock.app/Contents/MacOS/Xpra shadow --bind-tcp=127.0.0.1:10000
etc.pp.