Lambda Configs

config-mod.config

{ 
    /* This is a comment */ 
    "identifiers": ["minecraft:potato"]
}

ConfigMod.java

public class ConfigMod implements ModInitializer
{
    @Override
    public void onInitialize()
    {    
        Configuration<Config> configBuilder = FabricConfigManager.INSTANCE.newConfig("config-mod", Config::new)
                .property
                (
                        PropertyType.STRING_ARRAY, "identifiers", 
                        (config, array) -> config.identifiers = Arrays.stream(array).map(Identifier::new).collect(Collectors.toList()),
                        config -> config.identifiers.stream().map(Identifier::toString).toArray(String[]::new), 
                        new String[0], "This is a comment"
                )
                .build();
                
        System.out.println(configBuilder.load());
    }

    private static class Config
    {
        public Collection<Identifier> identifiers;

        @Override
        public String toString()
        {
            return String.format("Config [identifiers=%s]", identifiers);
        }
    }
}

output.txt

[main/INFO]: [STDOUT]: Config [identifiers=[minecraft:potato]]