Any null node in SnakeYaml is considered non-scalar and gets added to a count that has a limit of 50, so if you serialize a mostly empty doublechest inventory and later try and load it, a YAMLException will be called and you'll be returned with an empty YamlConfiguration. Wondering if a constructor could be added to YamlConfiguration that accepts a Yaml object so we can make our own implementation or if the limit of 50 in LoaderOptions could be raised.

https://www.javadoc.io/doc/org.yaml/snakeyaml/1.26/org/yaml/snakeyaml/LoaderOptions.html