HTML StandardFirefox63+Safari10.1+Chrome54+Opera?Edge79+Edge (Legacy)?Internet ExplorerNoFirefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android? 4.13.1 Introduction This section is non-normative. Custom elements provide a way for authors to build their own fully-featured DOM elements. Although authors could always use non-standard elements in their documents, with application-
