Test for elements that have pseudo-elements If you do not see a green bar with the text 'pass' below the element, it means that element cannot have a pseudo-element in the current browser.So far

Presto: none on hr.

Webkit: none on img, input.submit, input.button, input.password, input.text, input.search, input.url, input.email, select, option, textarea, progress, meter

Firefox: none on br, input (all types), select, textarea