Comment 1 for bug 1503193

Additionally it is necessary to uncomment 'novncproxy_base_url' on controllers and configure it to be the same as on computes (it should start with "https://") and restart nova-novncproxy services. If this is not done, the following error will be observed in logs:

ValidationError: Origin header protocol does not match this host.

This workaround was found here - https://bugzilla.redhat.com/show_bug.cgi?id=1204482#c9