As stated here by the ZigZag developer ( @Samantha ) and reported here by @drcoolzic, there’s a way to shorten the zigbee network scan interval putting the following code in configuration.yaml:
zha:
zigpy_config:
topology_scan_period: 20
20 is the scan interval in minutes (and is the lowest admitted value)
I set 119 minutes because every 2 hours my coordinator starts appearing offline (and it works).
Seems that in the near future will be added a service which allows to force the scan on demand like the zha_map.scan_now we talked about above. Until that time I will leave the zha-map custom component installed.