xvfb-run
Run a command in a virtual X server environment.
TLDR
Run the specified command in a virtual X server
$ xvfb-run [command]
Try to get a free server number, if the default (99) is not available
$ xvfb-run --auto-servernum [command]
Pass arguments to the Xvfb server
$ xvfb-run --server-args "[-screen 0 1024x768x24]" [command]