[removed] How to get parent element by selector?

Answer 1

simple example of a function parent_by_selector which return a parent or null (no selector matches):

function parent_by_selector(node, selector, stop_selector = 'body') {
  var parent = node.parentNode;
  while (true) {
    if (parent.matches(stop_selector)) break;
    if (parent.matches(selector)) break;
    parent = parent.parentNode; // get upper parent and check again
  }
  if (parent.matches(stop_selector)) parent = null; // when parent is a tag 'body' -> parent not found
  return parent;
};