I downloaded the MetricBeat zip from here
https://artifacts.elastic.co/downloads/beats/beats-dashboards/beats-dashboards-5.2.2.zip
and tried to import them to Kibana on elastic.co , using the "Saved Objects" tab.
I clicked on the "Import" button, choose a json file but nothing happened.
(*) It seems there is an error on the browser console:
TypeError: arr.map is not a function at FileReader.reader.onload