For the same reason Facebook puts a big loud warning in the developer console. People will follow any instructions they&#x27;re given. &quot;Press ctrl+shift+I and paste this in the box and you&#x27;ll get a free puppy&quot; &quot;Put this in your address bar and your crush will be revealed&quot; &quot;Go to about:config and double click this thing, and then click this link and we&#x27;ll show you nearby singles that want to hook up&quot;<p>Firefox add-ons essentially have full, unrestricted access to your computer. Locking this down good and well is pretty important.