I don't remember where I got this, but this is a custom query widget reporting the start time, end time, and duration of the daily maintenance on your SolarWinds Platform.
As configured it pulls events for the last 7 days, but can be configured for longer times by adjusting the -7
in line 44 to whatever duration you'd like. Be sure to change the Number of Rows per page setting in the Custom Query widget if you don't want pagination.