The :-moz-locale-dir(ltr) CSS pseudo-class matches an element if the user interface is being displayed left-to-right. This is determined by the preference intl.uidirection.locale (where locale is the current locale) being set to "ltr".
The :-moz-lwtheme pseudo-class matches in chrome documents when the root element's lightweightthemes attribute is true and a theme is selected.
The :-moz-only-whitespace CSS pseudo-class matches an element that has no child nodes at all or empty text nodes or text nodes that have only white-space in them. Only when there are element nodes or text nodes with one or more characters inside the element, the element doesn't match this pseudo-class anymore.
The :-moz-suppressed CSS pseudo-class matches elements representing images that were not loaded because loading images from that site has been blocked.
The :-moz-system-metric(images-in-menus) CSS pseudo-class matches an element if the computer's user interface supports images in menus.
The :-moz-system-metric(scrollbar-end-backward) CSS pseudo-class will match an element if the computer's user interface includes a backward arrow button at the end of scrollbars.
The :-moz-system-metric(scrollbar-end-forward) CSS pseudo-class will match an element if the computer's user interface includes a forward arrow button at the end of scrollbars.
The :-moz-system-metric(scrollbar-start-backward) CSS pseudo-class will match an element if the computer's user interface includes a backward arrow button at the start of scrollbars.
The :-moz-system-metric(scrollbar-start-forward) CSS pseudo-class will match an element if the computer's user interface includes a forward arrow button at the start of scrollbars.
The :-moz-system-metric(scrollbar-thumb-proportional) CSS pseudo-class will match an element if the computer's user interface uses proportional scrollbar thumbs; that is, the draggable thumb on the scrollbar resizes to indicate the relative size of the visible area of the document.
The :-moz-system-metric(touch-enabled) CSS pseudo-class will match an element if the device on which the content is being rendered offers a supported touch-screen interface.
The :-moz-system-metric(windows-default-theme) CSS pseudo-class matches an element if the user is currently using one of the following themes in Windows: Luna, Royale, Zune, or Aero (i.e., Vista Basic, Vista Standard, or Aero Glass). This will exclude Windows Classic themes as well as third-party themes.
The :-moz-tree-cell-text(hover) CSS pseudo-class will match an element if the mouse cursor is presently hovering over text in a tree cell.