I am trying to start firefox headless. The following is the beginning of the shell script that starts it:

Xvfb :99 >/dev/null 2>&1 &
sleep 3
firefox --display=:99 >/dev/null 2>&1 &

When this script is run, the following error occurs:

Xlib:  extension "RANDR" missing on display ":99".

I have tried starting Xvfb with the following, but it does not prevent the error:

Xvfb -extension RANDR :99 >/dev/null 2>&1 &


Xvfb +extension RANDR :99 >/dev/null 2>&1 &

Is there a better way to enable XRandR in Xvfb so that firefox is able to see the extension?

Alternatively, is there a way to disable XRandR in firefox?


Firefox now has a headless mode which doesn't require an X server (like Xvfb) at all. If you're reading this, you may want to investigate this as an alternative, as it's much simpler to work with.


Xvfb dose not implement Xrandr, the only way to enable is would be to implement it. So in that case just ignore this message or filter it out. Like

firefox | grep -v RANDR

or so...

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