When using a resource pack containing 3D models, they do not render correctly. Flowers, crops, grass, and some blocks show up as if there isn't a resource pack selected, but most blocks show up with the missing texture.
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old model format, you have to update the model format for the pack to work propperly
How do I do that?
Ryan Holtz's comment from MC-56987:
"I made a very public post on Reddit explaining that the block model format was going to be changing. Go get ahold of the authors of the models and tell them to update, this isn't a bug."
Thanks!