CentOS 7.x (tested on 7.1/7.2/7.3/7.4/7.5)
Foreman (installed by official installer, from repo) from 1.13 to 1.16.1

Effect:
1. When we do have overrides in parameters which are set to YAML, cloning group breaks YAML to something FOreman does not longer understands.
Example of YAML:

chocolatey-core.extension:
  ensure: latest
dotnet4.7.1:
  ensure: latest
conemu:
  ensure: latest
wget:
  ensure: latest

The hostgroup is currently in AAA\hostgroup-a, using environment prod
Moving hostgroup to BBB\hostgroup-b, still using environment prod, breaks YAML to this form

--- "chocolatey-core.extension:\r\n  ensure: latest\r\ndotnet4.7.1:\r\n  ensure: latest\r\nconemu:\r\n
  \ ensure: latest\r\nwget:\r\n  ensure: latest\r\n" 

2.This of course breaks puppet on next run, and forces us to create or move groups manually - by creating new group and copy/paste whole content.

What's to be expected:

- YAML not being changed.