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Allowing tags in block.properties entries or any other properties, would make support for modded blocks soooooooooooooo much easier. Instead of adding every single block from a mod, we can literally just add something like #minecraft:leaves, and that would include all modded leaves that use that tag. This even means that shaders can work on newer versions without any updates (aslong as the new update dosen't break the shader code), because the blocks from the new minecraft release will likely be added to these tags as well.

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Inside of block.properties (or any .properties file), allow users to add tags into the properties file. This adds a layer of abstraction into these entries meaning you don't have to explicitly put in every single block. You could even add a feature where shader pack devs or modpack devs can exclude certain blocks, so even if they exist inside a tag, they won't actually be applied. To support double plants (where shaders would use half=lower/upper to define them), iris could detect if a plant is a double plant, and then create two seperate tags that the shaders could use, containing the lower and upper halfs for them.

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The only alternative to get this to work would be to add every single block from every single mod that adds modded leaves/plants into the block.properties file, which you can also mess it up and leave things out, and also means that you have to constantly update it with each release.

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