Open the UI, go to any page. It will be shown immediately.
Once it's rendered, click the same page from the left nav (for example: if you were on the Deployments page, then click "Deployments" on the left-nav).
It will take about 10-15 seconds for the widgets to load.
Already known issue: CYBL-486. Closed this one as duplicate.
, : Please discuss and prioritize CYBL-486.