Xvfb

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Xvfb or X virtual framebuffer is a display server implementing the X11 display server protocol. In contrast to other display servers, Xvfb performs all graphical operations in virtual memory without outputting to any screen. From the point of view of an X client app, it acts exactly like any other X display server, serving requests and sending events and errors as appropriate. However, the frames are not necessarily displayed on a screen. This virtual server does not require the computer it is running on to have any kind of graphics adapter, a screen or any input device. Only a network layer is necessary. Xvfb supports several X Protocol Extensions, such as Compositing and OpenGL GLX support via Mesa.

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