In the comments for this enhancement request there is a suggestion (comment 5 at 2012-03-13 15:57:41) to set media.webm.enabled
, media.ogg.enabled
and media.wave.enabled
to false
in order to "render <video>
and '' elements unable to play anything."
All these options are readily available if you enter about:config
in the address box, and then enter media.
in the filter box. In my testing (Firefox 10.0.1 on Gentoo) it was not necessary to restart Firefox, the elements were disabled when I reloaded the page.
This page was useful for my tests. The video there is disabled when both media.webm.enabled
and media.ogg.enabled
are set to false, as there is fallback from one to the other.
There were rumors reently that future Firefox will support h.264, in that case you might have to disable that too after an update.