Thanks! I'd checked this out. Unfortunately this project builds an iMessage app not a sticker pack. The difference is it shows up in the app drawer not sticker drawer. By sticker drawer, I means when you click "+" in iMessage, and then in the opened menu you select "Stickers". Now you can see all the sticker packs listed horizontally at the top of the input sheet. The demo app isn't there.
All the existing sticker packs I listed in my original post are in Sticker drawer, with custom UIs.
Zote
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