Mozillatude often comes in the form of a question, thrown back in one's face: "Why would you want to do that?" or "If it bugs you, why don't you stop complaining and fix it yourself?"
Term comes from the seemingly overly-prevalent attitude among those responsible for the development of Mozilla-family Internet products (Firefox, Thunderbird, Mozilla Suite), especially after an issue or complaint has been brought up.
"Do you know why you can't use the 'Insert' key on your keyboard to overtype text in Firefox or Thunderbird? Answer: Mozillatude!"