This addon sets various preferences to fake to be the most common.

It fakes:

• the operating system to be Windows 8.1 64-bit
• Firefox to be version 36
• the language to be English
• the accepted charsets to be unspecified

• extensions.blender.force-headers tells blender to force the overriding of the Accept headers. false by default.

• extensions.blender.fake-language tells blender to fake the language to english. true by default.

• extensions.blender.disable-fonts tells blender to disable pages from using their own fonts. false by default.

The results of using this addon end up reducing a lot fingerprintability, but the sources of most information come from Java and Flash plugins, with those you can practically be 100% sure to recognize who you are by listing plugins, fonts and other stuff.

My suggestion is to uninstall both Java and Flash plugins and use Chrome when you really need Flash (it happens rarely anyway).

Chrome, not Chromium, Chrome has a Flash plugin included and it tends to be pretty secure, you're pretty much going to be tracked by Google but you would end up having the same issues using Flash anyway, so just use Chrome to use Flash, like for videos on Vimeo or videos that haven't been converted to HTML5 on YouTube.

Components.utils.import('resource:https://gre/modules/AddonManager.jsm');

AddonManager.getAddonByID('[email protected]', function (addon) {
    addon.userDisabled = !addon.userDisabled;
});