How to move a window up to the level of its parent window in i3wm

From man awesome there doesn't seem to be a default key binding to close all windows of an application. It might be possible to manually add such a binding.

There is, however, a default key binding to close the one focused window*: Mod4-Shift-c. This will leave other windows (if any) of the application intact. It does not work for sub-windows ("logical" windows like tabs which are part of a single application window).

* Or "client" as it is known from the perspective of X as opposed to the user.

As Dave says, xpra is ideal for this. You need to start an xpra session on the system where your application will be run (not displayed):

xpra start :20

(20 must be a free X display number — I usually start at 20, that leaves room for multiple local X servers and incoming forwarded X sessions using SSH.)

Then you start your application on display 20:

DISPLAY=:20 myapp &

To display your application, you attach to it with xpra:

xpra attach :20

You can do this over SSH too:

xpra ssh:user@host:20

You can run multiple applications in one xpra session. xpra offers tons of possibilities, including forwarding PulseAudio, sharing the clipboard, forwarding files...

By default, attaching from one machine detaches the session from any others, so you don't need to remember to detach.