When upgrading a diamond armor piece that has netherite trimmings to netherite armor, the netherite trimming is kept on the netherite armor. Armor pieces should not be able to have trimmings of the same material.
Steps to reproduce:
Add any kind of trimming with a netherite ingot to a diamond armor piece
Upgrade the diamond armor piece to netherite
Result: A Netherite armor piece with netherite trimmings
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We're tracking this issue in MC-259356, so this ticket is being resolved and linked as a duplicate.
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