This is an experimental technologyCheck the Browser compatibility table carefully before using this in production. The TransitionEvent.pseudoElement read-only property is a DOMString, starting with '::', containing the name of the pseudo-element the animation runs on. If the transition doesn't run on a pseudo-element but on the element, an empty string: ''. Syntax name = TransitionEvent.pseudoElement Specifications Specification Status Comment CSS TransitionsThe definition of 'TransitionEvent.pseudoElement' in that specification. Working Draft Initial definition. Browser compatibility Desktop Mobile Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari Basic support (Yes) 23.0 (23.0) No support (Yes) No support Feature Android Webview Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile Basic support (Yes) (Yes) 23.0 (23.0) No support No support No support See also Using CSS transitions transition, transition-delay, transition-duration, transition-property, transition-timing-function.