I'm not sure why this happens or how to fix it... usually it just fixes its self within moments or hours (never really consistent). But some how the partition visuals just disappear. Unfortunately with them gone the "Clear Cache" button goes missing as well. Sometimes if I hit recalculate it will magically all come back but even that is not consistent. This current instance has taken an hour and still nothing so I'm hoping to find a realistic solution for when this happens.
Normally this looks like this: