-moz-appearance

This paragraph is styled with -moz-appearance: button (and, to make it more readable, has 1em of padding). That doesn't make it a button of course. You can't focus it, clicking on it has no effect (beyond the visual changes that are merely caused by the -moz-appearance property).

1. This is an HTML ordered list.
2. Each list item has the -moz-appearance of a checkbox.
3. The parent element has the appearance of a scrollbartrack-vertical.
4. Notice how this is just HTML. No native widgets anywhere!