Minecraft version: 1.16.5
Chisel version: 2.0.1-alpha4
Forge version: 36.2.26

Mods that may interfere with rendering:
Magnesium (+extras), Sulfuric, Optifine is NOT present

The problem:
When placing chiseled blocks there is a weird rendering issue where the blocks aren't properly connected or textured, can be fixed by using f3+a.

images demonstrating it below



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This is a bug caused by element mods (Sodium, Magnesium, etc.) and their attempt at concurrent rendering.

Any idea how I might fix that?

Any idea how I might fix that?

not use any rendering modifying mod other than optifine/connected textures
This is probably more of a compatibility issue on their end

Or report it to the mod actually causing the issue.

Yeah that's a good idea

Or report it to the mod actually causing the issue.