Elements Side Panel

From FirebugWiki

The Elements side panel lets you try out CSS selectors and lists all matching elements on the page. Selectors can be entered via the Try a selector... field or by right-clicking a selector inside the CSS Panel and choosing Get Matching Elements from the context menu.

Doing so will list all elements, that match the entered selector.

[edit] Context Menu

The context menu for the matching elements is the same as for the HTML elements inside the HTML panel.