Do not use the door as a work surface unless the manufacturer expressly permits a specified load. Hinges and glass are not substitutes for a stable heat-resistant counter.
What the observation means
A heavy dish adds leverage to the open door and may cause damage or movement. Children standing or sitting on it create an even greater risk. A door that still closes afterwards is not proof that no damage occurred.
A useful next step
Place cookware on a suitable surface and keep weight off the door. If it sagged, creaked sharply or changed alignment after being loaded, stop using it and arrange assessment. Do not bend it back or tighten random hinge fasteners.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.