getSelector.js

function getSelector(el){
  let nodes = [],c,e,d=el.ownerDocument,h=d.documentElement;
  do{if (el.id){ nodes.push(`#${el.id}`); break;
  }else{  if (el==h) c=0; else for (c=1,e=el;e=e.previousElementSibling;c++);
    nodes.push(c?`:nth-child(${c})`:el.tagName.toLowerCase());
  }  } while ((el=el.parentNode)&&el!=d); return nodes.reverse().join` > `;
}