With 0.110. internal_url and external_url were introduced to the configuration. The screenshot in the blog entry shows the external_url being https:// with a domain name and the internal_url being http:// with an internal IP. In practice, I have found that what the screenshot shows is impossible.
When https is enabled the port hass is bound to will no longer serve unencrypted traffic. Entering https:// with the internal IP address, will cause whatever client connecting to fail with a SSL certificate error because the certificate’s common name will belong to the domain name of the external_url and not the internal IP address.
Unless I am mistaken, with under most circumstances unless you have a wildcard SSL certificate https the internal_url and and external_url will have to be the same.