4 ms·Firefox supports H.264 on Mac via the QuickTime plugin.by taligent 14y agoFirefox supports H.264 on Mac via the QuickTime plugin.av500 14y agoFirefox supports H.264 on Linux via the Flash plugingcp 14y agoFlash has historically always been used to deliver H264 to Firefox, though. That's not quite the same as the browser supporting it in <video>.