Firefox may be the base for Comodo Dragon and Ice Dragon, but those browsers aren't built by Mozilla. There is no "family" relationship , other than they are free to use Firefox code to built their own version, that has a unique name and different "branding" as far as icons and other trademarks / copyright property that is owned by Mozilla. They can add or change features at will and not have to ask Mozilla for permission as they are "3rd party builds".

If you would like to see that type of feature in Firefox, please provide feedback to Mozilla here: https://input.mozilla.org/en-US/feedback

Or file a detailed Bugzilla report here, as RFE - Request For Enhancement: https://bugzilla.mozilla.org/ See this first: https://developer.mozilla.org/en/Bug_writing_guidelines

The current release of Comodo Dragon is based on Chromium, not Gecko: https://en.wikipedia.org/wiki/Comodo_Dragon

Since new features can take a long time, how about an add-on?

https://addons.mozilla.org/firefox/addon/happy-bonobo-disable-webrtc/