openhab-android: remote openhab-cloud instance + Android App: cannot load sitemap in app only

I am running openhab 2.2 snapshot and a dockerized instance of openhab-cloud.

My openhab-cloud instance is accessible via an opened port from my router and a URL supplied by a DDNS service.

I can access openhab-cloud via http://<my-domain>.com:8000 in a browser

I can access my openhab sitemaps via http://<my-domain>.com:8000/basicui/app?sitemap=default

When I enter http://<my-domain>.com:8000 and my username and password for openhab-cloud into the android app, I can successfully connect to the openhab-cloud instance and receive android notifications. However, the app does not successfully load the sitemap or give me any kind of error message. The loading icon in the upper right corner continuously refreshes, but never finishes.

Is this a bug, or is there something I am missing?