Updating to the latest update you encounter an error on startup.

"net.minecraftforge.fml.ModLoadingException: The Undergarden (undergarden) encountered an error during the common_setup event phase
§7java.lang.NoSuchFieldError: STEP_HEIGHT
at net.minecraftforge.fml.javafmlmod.FMLModContainer.acceptEvent(FMLModContainer.java:111) ~[javafmllanguage-1.20.1-47.2.0.jar%231046!/:?] {}
at net.minecraftforge.fml.ModLoader.lambda$postEvent$29(ModLoader.java:326) ~[fmlcore-1.20.1-47.2.0.jar%231045!/:?] {}"

crash-2024-02-15_23.10.02-client.txt

youre gonna have to use neoforge for now, the field is named differently on forge