Binary package “xpra” in ubuntu precise
tool to detach/reattach running X programs
Xpra gives you the functionality of GNU Screen for X applications.
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It allows the user to view remote X applications on their local machine, and
disconnect and reconnect from the remote machine without losing the state of
the running applications.
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Unlike VNC, these applications are "rootless". They appear as individual
windows inside your window manager rather than being contained within a single
window.