I have setup the xvfb server on my headless server and when I m running the DISPLAY=:99 firefox I am getting this exception missing RANDR extension
Many of them said to disable some xinerna from the xorg.conf file but this file is not getting created in my case.
So I am searching for how to add the missing RANDR extension.
First off, Xvfb doesn't read configuration from xorg.conf. Xvfb is a variant of the KDrive X servers and like all members of that family gets its configuration from the command line.
It is true that XRandR and Xinerama are mutually exclusive, but in the case of Xvfb there's no Xinerama in the first place. You can enable the XRandR extension by starting Xvfb using at least the following command line options
Xvfb +extension RANDR [further options]