I apologize this is a really horrible bug report, I just remembered it now but I don't have screenshots or anything like that.

It's honestly not even an issue, just a funny thing I noticed.

I'm playing BTV in my 1.12.2 pack and I had a shoggoth build the Shrine structure. The structure has chiseled elder bricks going in two circles around it, as well as a circle of normal elder bricks.

Well, right in the corner, just one of the chiseled elder bricks is normal elder brick for some reason. I checked all the other corners, all chiseled.

It could probably just be a bug when my shoggoth built it, or it could be a problem with the coded input for what the shoggoth is supposed to build.

Regardless, it's a single block that honestly makes 0 different and is almost not even noticeable, but I noticed it and figured I may as well bring it up.

Wouldn't hurt to double-check the structure file or whatever just to make sure.
To reproduce,if the shoggoth builds it right for you, then it's just a bug on my end.