Getting rid of the _cmsinternal in the site preview links from the Experience manager
If and only if the CMS runs on a different hostname than the site(s), you can skip the _cmsinternal prefix. In that case, the CMS and sites do not share the same HTTP session, and therefore, we do not need to indicate in the URL that we are looking at a preview.
To skip the _cmsinternal prefix, you can set the hst:cmspreviewprefix property of the hst:hosts node to an empty String value. You can do this through bootstrapping (recommended for smoother upgrades) and/or directly in the CMS Console (for immediate effect). To bootstrap this change, add the following YAML to the repository-data-site module:
definitions: config: /hst:hst/hst:hosts: hst:cmspreviewprefix: ''