When on the Monitored Devices page, choosing any device from any Collection or using the "Search Quick Filter" you would expect the Details pane on the right to populate data, least it has in the past. Now at least since 21.2.6 this pane never populates data, you have to choose any other tab on the right, like Polled Metric Families, Monitoring Profiles ect. THEN coming back to the Data tab shows the data available on that tab.
Details page not showing in monitored devices when a device is selected.
The issue here one of the SNMP profiles has a '\' in the name and this is causing an exception and the tab to not load.
Release : 21.2
Component : Performance Management Portal Web UI
Remove the '\' from the name of the SNMP profile.