Locking of input in a search dialog when a property is passed as a search criteria

I am able to modify greyed-out classification property which was passed as a search criteria for 'Part' itemtype. I want that property to be locked and user should not be able to modify it by any means.

I created one new dummy Part item, set its classification property and used that dummy item in the search criteria.

In this screenshot, even though my item Class is greyed-out but I can still change it by clicking on three-dots button under Item-Class. What I can do to not make it happen ?