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Issue description:when i open minecraft end enter in my world, my game crash and send me this error

The game crashed whilst ticking block entity
Error: java.lang.IllegalArgumentException: Cannot get property PropertyBool{name=on, clazz=class java.lang.Boolean, values=[true, false]} as it does not exist in BlockStateMachine{block=mekanism:machineblock2, properties=[active, facing, recipe, tier, type]}

i use the versione 1.12.2

same1 can pls help me ?

a) that is not nearly enough information
b) we no longer support 1.12

I have an old world of Minecraft and I have updated the mod in the package that I use for this world and I have updated the mekanism, since I have updated it if I enter the world my game crash and it only gives me this errors

a) that is not nearly enough information
b) we no longer support 1.12

No idea what is going on, seems like something went wrong during the upgrade process. Your best bet would be to upgrade fewer versions at a time because maybe the data fixers had some edge case they didn't handle properly.