Optimum Realism R2.8.0 Connected Textures Required
Summary
On Optimum Realism this announcement warns that starting R2.8.0 the pack requires Connected Textures via Optifine or Continuity on Fabric/Iris. Players must enable or download these mods before playing to see most textures, as more blocks use connected textures. Visit the Patreon post for details and troubleshooting.
Starting R2.8.0, you won't be able to play Optimum Realism without turning on Connected Textures on Optifine or using Continuity on Fabric/Iris. Please make sure that you enable/download before playing - as with more and more blocks using this feature - you're missing out on most of everything the texture pack offers to you.
https://www.patreon.com/posts/112501651

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