clipboard.js

[Costas]

Modern copy to clipboard. No Flash. Just 3kb gzipped.

https://clipboardjs.com/
https://github.com/zenorocha/clipboard.js

or pure javascript :

tested and working on Chrome

//src - https://komsciguy.com/js/a-better-way-to-copy-text-to-clipboard-in-javascript/

function copyToClipboard(text) {
  const listener = function(ev) {
    ev.preventDefault();
    ev.clipboardData.setData('text/plain', text);
  };
  document.addEventListener('copy', listener);
  document.execCommand('copy');
  document.removeEventListener('copy', listener);
}