Previously posted at pimp-my-rig is a tutorial to force add-on compatibility with Firefox. It still works. For third party add-ons that are installed via Program Files, like DivX, here is another tweak to force compatibility with Firefox. We tested it on Firefox 6.0 and it works just as well.
All those works, why post another procedure? Well, as the saying goes "there are a thousand ways to kill a cat" -- so does this tweak. With the release of Firefox 6.0, most addons will not be compatible. The above tweaks work for a variety of addons, here is another way to force compatibility check.
Open an Explorer window and browse to "%appdata%\Mozilla\Firefox\Profiles" (this is the default directory containing your Firefox user profile). Inside this directory will be another folder named xxxxxxxx.default (xxxxxxx is a string that will differ from computer to computer); and inside this is the extensions folder, which is the directory that contains the extensions or addons you have installed (refer to screenshot below).
WinRAR can open those XPI files in the extensions folder. Once opened, you can edit the install.rdf files inside the archive.
Just look for the string "<em:maxVersion>" and/or "</em:maxVersion>". Enclosed in these XML tags is the maximum version of Firefox that is compatible. Change it to "6.*" or "7.*" as you wish. Then save the file and update the XPI archive.
Restart Firefox and test the functionality of the addon. As of this writing, downloadthemall is tested to work using this tweak on Firefox 6.0.
So if you need the functionality of your addon try this out.
