The add-on contains 5 backpacks, they are meant to help players on adventures around the world, backpacks made of 3d block with inventory interface drop backpacks made of 3d breastplate.
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Changelog
I talked more about all addons backpacks so that you understand how it works
Como hago que las coss se queden en la mochila sin que se salgan a la hora de llevarmel.