Rated 5 out of 5 stars
@Mike who said this was 'useless' and 'flawed'. Extensions are built by users, not by the Mozilla Firefox team. Most of them do not earn any money, but they Do listen to their users. Packaging the functionality of this into a toolbar is easy, and so is adding support for more BBCodes - you could ask the developer for this feature or hack it in yourself or ask a friend. LIke most extensions here this is based on a Public License, so unlike with a proprietary plugin (such as the numerous ones available to Internet Explorer) it is _not_ illegal to modify or fix it.
As such there are many extensions that had humble beginnings (like this maybe just as a context menu) but grew to something more usable over time. Certainly throwing tantrums doesn't help the situation. Surely you can use another browser but you will not find anybody who is going to build you a plugin that does exactly what you want on the first attempt and without any input.
Also, look at your requirements "a way to make bbCode buttons on forum websites work" do really believe that this is a common goal for all and any users of web sites? I believe this is quite nice funtionality to live in an extension, as it is clearly not of interest to the average user.