xvfb 2:1.20.1-1ubuntu1 (amd64 binary) in ubuntu cosmic

 Xvfb provides an X server that can run on machines with no display hardware
 and no physical input devices. It emulates a dumb framebuffer using virtual
 memory. The primary use of this server was intended to be server testing,
 but other novel uses for it have been found, including testing clients
 against unusual depths and screen configurations, doing batch processing with
 Xvfb as a background rendering engine, load testing, as an aid to porting the
 X server to a new platform, and providing an unobtrusive way to run
 applications that don't really need an X server but insist on having one
 anyway.
 .
 This package also contains a convenience script called xvfb-run which
 simplifies the automated execution of X clients in a virtual server
 environment. This convenience script requires the use of the xauth
 program.
 .
 More information about X.Org can be found at:
 <URL:https://www.x.org>
 .
 This package is built from the X.org xserver module.