title: How Do I Mock MSAL Authentication?
body: <p>I have added authentication to my web app using MSAL which connects to Azure Active Directory B2C.</p>
  <p>This works fine when I am connected and can access the Microsoft site. However, it fails when I am not.</p>
  <p>e.g. on a plane or in a firewalled build server</p>
  <p>How do I add mock authentication so that I can develop offline?</p>