utils.js

const removeUnless = (key) => {
	Array.from(document.querySelector('.nav-stacked').children).map(item => {
		if (item.dataset.category !== key) {
			item.parentNode.removeChild(item);
		}
	})
}

const copyToClipboard = str => {
  const el = document.createElement('textarea');
  el.value = str;
  document.body.appendChild(el);
  el.select();
  document.execCommand('copy');
  document.body.removeChild(el);
};