The :-moz-ui-invalid CSS pseudo-class represents any validated form element whose value isn't valid based on their validation constraints, in certain circumstances. This pseudo-class is applied according to the following rules:
The :-moz-user-disabledCSSpseudo-class matches elements representing images that were not loaded because images have been entirely disabled by the user's preferences.
The non-standard -moz-float-edgeCSS property specifies whether the height and width properties of the element include the margin, border, or padding thickness.