Copper trapdoors aren't in the 'trapdoors' part of the creative inventory.

Under the 'construction' tab, in the 'Trapdoors' drop down, copper trapdoors don't appear. 

(They probably SHOULD appear.) 

Please make them appear. 

If copper trapdoors aren't trapdoors, that's okay then. But rename the 'trapdoors' button into 'Wooden Trapdoors'

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