When an inserter is disabled by a circuit condition or logistic condition, the status is "Waiting for source items". When rotating the inserter (by pressing 'r' on it), the status becomes "Disabled by control behavior". The status reverts to "Waiting for source items" a...

When holding an offshore pump, icons appear at the edge of the water to show where the pump can be placed.
When holding a blueprint of an offshore pump, these icons do not appear.