> Good to know that Linux has finally joined the fresh tech wave of the 90's and copied that basic useful function.

I don't think anyone has said that Linux didn't do this in the 90s too, e.g. KDE supports this since KDE2, released in the year 2000: https://en.wikipedia.org/wiki/K_Desktop_Environment_2

In pretty much its current transparent form, though more protocols have been added since.

Not sure what CDE supported, which I think was the big pre-Gnome/KDE UI.