The ::-moz-progress-barCSSpseudo-element applies to the area of an HTML <progress> element that represents the amount of progress that has happened so far. This lets you, for example, change the color of progress bars.
The :-moz-first-nodeCSSpseudo-class represents any element that is the first child node of some other element. It differs from :first-child because it does not match a first child element with (non-whitespace) text before it.
The :-moz-focusringCSSpseudo-class is similar to the :focus pseudo-class, but it only matches an element if the element is currently focused and a focus ring or other indicator should be drawn for that element. If :-moz-focusring matches, then :focus also matches, but the converse is not always true - it depends on whether the user agent has focus ring drawing enabled and how the element was focused. Whether the user agent has focus ring drawing enabled can depend on things like the settings of the operating system the user is using, so the precise behavior of this pseudo-class can vary from platform to platform depending on each platforms' particular focus best practices (defaults) or user modified settings.
The :-moz-last-nodeCSSpseudo-class matches an element that is the last child node of some other element. It differs from :last-child because it does not match a last child element with (non-whitespace) text after it.