Check whether the shelf or pocket was repositioned recently. Not every combination of mounting slots provides clearance for every fitting.
What the observation tells you
A shelf inserted backwards or not fully seated can extend farther forward than intended. The door may then compress the contact point each time it closes, eventually cracking plastic even though the seal appears normal.
A useful next step
Unload the affected fittings and compare them with the model diagram. Refit only owner-removable components as directed. If the correct arrangement still makes contact, obtain advice about damaged supports rather than trimming an edge.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.