title: Return Input from Custom Popup
body: <p>I am currently working on a custom modal popup entity. When I need a text value from a user, I make the HTML element visible, then I need to get the value they enter in the text field when they press the "Enter" button. </p>
  
  <p>The problem is that what I'm trying to do doesn't seem to have an easy implementation. I don't think it's possible without Promises, and all attempts so far have not worked. Any ideas on possible solutions?</p>