Faced the below issue when trying to access backoffice after starting of the server.
The issue being reported is intermittent and in pre prod environment.
Version : 1808.20
Failed to render widget [id='explorerTree', definitionId='com.hybris.cockpitng.widgets.common.explorertree', message='null']
Attached console log for reference.console-log.txt
Backoffice snapshot: