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Just bought shaderforge and I'm still getting this error (1.27).

get_skinIndex is not allowed to be called from a ScriptableObject constructor (or instance field initializer), call it in OnEnable instead. Called from ScriptableObject 'SFN_Append'.

get_skinIndex is not allowed to be called from a ScriptableObject constructor (or instance field initializer), call it in OnEnable instead. Called from ScriptableObject 'SFN_ComponentMask'.