On: Emacs is my new window manager

[jaccarmac]

I'm not familiar with X internals and am not sure if it's the same thing, but EXWM basically allows that (browsers run in buffers).

[svlasov → jaccarmac]

Yes, that's possible. You can set any X11 window as a child of another X11 window, the parent window will be responsible to manage (taking care of window geometry and what not) child windows.