Comment 0 for bug 610172

We usually want to run our tests headless, so both test_on_merge and the testresources config cause xvfb-run to be invoked. This is code duplication, and is also inefficient, because xvfb may not be needed to run the specified tests.

Instead, it would make sense to invoke xvfb only when running windmill tests, and to turn off xvfb according to a commandline flag like "--show-browser".