javascript:(function(){var allCustomElements=[];function isCustomElement(el){const isAttr=el.getAttribute('is');return el.localName.includes('-')||isAttr&&isAttr.includes('-');}function findAllCustomElements(nodes){for(let i=0,el;el=nodes[i];++i){if(isCustomElement(el)){allCustomElements.push(el);}if(el.shadowRoot){findAllCustomElements(el.shadowRoot.querySelectorAll('*'));}}}findAllCustomElements(document.querySelectorAll('*'));allCustomElements.forEach(function(el,i){el.style.outline='1px dashed red';el.style.backgroundColor='rgba(255,0,0,0.1)';});})();