Rudder

This is the expected behaviour: if you don't change anything, there is no call for a change message. If you forgot your change message in the previous event, well, three options:

1. You shouldn't have forgotten it :-)
2. Enable the "mandatory" option for change messages, to enforce their entry in the UI
3. We may need another feature, such as adding comments to Event logs, Groups, Directives, etc... to add information to existing objects/events.

Either way, what is most confusing here is that an event log is generated anyway, even though there is no change. This is caused by the promise regeneration. I think the best solution here is to not launch a promise generation if there were no changes (we clearly know how to detect this, since we don't log the event). This will be addressed in #3191.