title: Visual Studio Error undefined or null reference baseUri
body: <p>This is the error I get when I try to start the Office add-in in a browser:</p>
  
  <p><img src="https://i.imgur.com/dYAL8qW.png" alt=""></p>
  
  <p>What is this <code>baseUri</code>, where can I change it, and to which value would I change it?</p>