Cauldrons, Flower Pots, Hoppers, Redstone Comparators, Redstone Repeaters, Tripwire, Vines do not use the multipart, and it uses up more file capacity than it should. I have a solution resource pack, which decreases about 70kb.
I know this is kind of a suggestion, so I don't mind being this bug to be invalid, or WAI, but I will be very happy if this pack was used. It took me a few hours to make this pack.
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