Problem with coordinator backup (empty)

[UsefulVid]

I am using z2m as a Home Assistant addon. All works fine besides the coordinator backup.
The coordinator_backup.json has an up to date timestamp but the device section is empty.
My coordinator:

Sonoff ZBDongle-E (V2 model) 
Coordinator-Typ
EmberZNet
Coordinator-Version
7.4.2 [GA]

In my addon config "ember" is configured.

@Nerivec may help out :)

I have been told what my coordinator supports backup and also ember/eszp supports it, besides the (outdated?) FAQ.

Need some help to get backup running.

[Nerivec]

Backups from ember (& old ezsp) do not have the devices section (empty). This section is for APS link keys, which is not used in current configuration.
In short: your backup is correct as long as it has everything else (you would get an error if not).