Material is opaque instead of cutout after build

My game looks like this in editor:

When I build it as executable (Windows Intel 64 bit) it looks like this:

I have no idea why it is this way. Currently Iam using Unity 2021.3.2f1. This never happened to me with 2020.3.20f1.

Any idea why this is happening?

Have you gotten the answer? I have the same problem and can’t find a solution.