Move away from X-only stack

[savchenko]

Given the general movement towards Wayland and deprecation of X-server, moving away from the Marco, etc. and aligning closer with the upstream XFCE4 developments might be a good idea.

Perhaps a self-contained GTK3/4 theme + icon pack would be a good start.

Thoughts?

[User738git]

I don't know how I would approach that since marco allows a gradient titlebar; something which xfwm doesn't. There are probably other alternatives, but the easiest one to install was marco. Marco will probably come with Wayland support in the future anyway (I hope).