Javascript - prompt cause 'document is not focused'

Question

If I add a prompt to the function it works once, but gives the error:

"Uncaught (in promise) DOMException: Document is not focused" at the second attempt.

This is the code:

function site(str) {
  var url = prompt();
  var text = 'The URL is ';
  (async() => {
    await navigator.clipboard.writeText(text + url);
  })();
}

<button class="button" onclick='site()'>URL</button>

I've asked my best friend, Google, but I can't find any solutions. What am I doing wrong?

Answer 1

It is probably caused by this bug in chromium (Issue #1085949) which makes your prompt call take focus from the Document and not return it when closed. I was not able to reproduce this issue on Safari and Firefox.

The same bug can be reproduced by doing alert instead of prompt followed by navigator.clipboard.writeText.

Answer 2

Your JS may be running on a child page. The following works for me:

await parent.navigator.clipboard.writeText('text to copy to Clipboard here.');