Http_post_session_empty error

We are using intercom in a React SPA. Calling shutdown followed by boot is causing an error. Here’s the relevant code:

if (!user) {
    aWindow.Intercom('shutdown');
    aWindow.Intercom('boot', {
      app_id: 'our-app-id'
    });
  }

The above code causes the following error in the developer console:

http_post_session_empty

Any idea why this is causing an error? Intercom loads and seems to work in spite of the error.

Thank you,

Troy