Login button disabled when signing in to Trello for OAUTH


I have a customer of my app (Kanbann) who sees the login button as disabled, when trying to login to Trello as part of the OAUTH. It works for me. Do you have any suggestions or idea as to why this might be happening for them?


We have in-line javascript on that page that enables the button after 3 seconds:

function setup() {
    // don't allow authentication until 3 seconds have passed
    setTimeout(function() {
      document.getElementById('approveButton').disabled = false;
    }, 3000);

Are they waiting for 3 seconds? If so, do they have javascript enabled?