We have noticed in recent (so cannot relate to specific portal version) that the dashboard seems to get cached.
IE work item IR123 was on the report for missing a support group assignment.
Opened the work item and assigned to a support group
Returned to the dashboard and work item was still listed.
Waited 5 minutes for background workflows to run but item remained on report
Until the browser was closed and reopened the dashboard did not update
But once browser was reopened work item cleared from report.
Wondering if others are seeing this.