What are these artifacts? Triangles on my glass material. Any news on how to solve this?

Has anyone firgured out how to get rid of these artifacts?

I followed this tutorial to get the glass material going.

The Vertex Color painting part was not necessary because I had it setup already. Anyway, the artifacts won’t appear near the edges. Setting the material to “Two Sided” was my first attempt. No luck!

Normals, likely.

I had normals checked, none of them were inverted. I gave it another try before I read your reply, though. This time, I subdivided the original mesh. Guess what? More triangles. Any clues?