Visual artifact with Customizable Player Models in iris 1.7.1+mc1.21

[src3453]

What happened?

in 1.21 version of Iris, Customizable Player Models will not be shaded correctly.
in 1.20.4, it not be happen.
any shaders wont be rendered correctly. (i tested with SEUS Renewed v1.01, Complementary Unbound v5.2.1, project LUMA v1.32, all of them could not rendered correctly.)

Screenshots

in Iris 1.7.1+mc1.21: can not shade correctly

in Iris 1.7.1+mc1.20.4: can shade correctly

Log output

No response

Minecraft Version

Minecraft 1.21

Iris Version

iris 1.7.1+mc1.21

Operating System

Windows 11 (kernel ver 10.0.22631.3737)

What is your GPU?

AMD Radeon RX 7600 8GB

Additional context

No response