version: forge 28.2.3, IE #bcdad966, compiled on testing machine.

The Strip Curtain item y offset is about 2 blocks too high (3 blocks above the ground level):

First look: The datagen output of strip_curtain.json item model contains:

    "ground": {
      "translation": [
        0.0,
        3.0, <<<<<<
        0.0
      ],