[ME] Updating to MaterialEditor 3.13.2 and above breaks IBL_shader_alpha

[megu230]

After updating ME to the version mentioned in the title, IBL_shader_alpha stops rendering correctly, as demonstrated in the images. Rolling back to 3.13.1 causes the shader to behave as expected. Copying edits and pasting it in the same material in 3.13.2 causes the shader to behave normally, but after saving and loading the card, the shader returns to its bugged behavior.

Expected behavior:
https://files.catbox.moe/hr9lv6.png
https://files.catbox.moe/j4m7ct.png

Actual behavior:
https://files.catbox.moe/7k9yia.png
https://files.catbox.moe/qc6f9r.png