title: How to create an overlay and load it in Firefox
body: <p>Hey guys I have began some introductory level Firefox Add-ons programming. I am trying create an add-on that has an overlay on the screen that has 5 text boxes. The purpose of the text boxes is it will alter 5 different Textbox nodes on a specific webpage (the webpage is an internal page at my job). I am looking to create an overlay that is similar to this </p>
  
  <p><a href="https://i.stack.imgur.com/36TPb.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/36TPb.png" alt="enter image description here"></a></p>
  
  <p>Instead of it saying Firefox Hello it would have 5 textboxes instead. I am unsure how to load it.</p>