The added feature is automatic lowering and latching of the paper tray's paper platform as the tray is withdrawn.
The feature consists of a linear cam in the chassis' left side way, and a corresponding actuator attached to the left side of the tray's paper platform. When the tray is withdrawn, the cam strikes the actuator and forces the paper platform down. Owing to the cam's position, it interferes with complete closure of early trays.
There appears to be no retrofit available.
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