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Additionally the configuration loads conf/attribute-resolver.xml. The default resolver does not specify any attribute encoders, but referencing the file allows use of encoders for exceptional cases if you prefer to use them.
Upgrades From V3
Upgraded systems with an older services.xml file are configured internally to load only the existing AttributeResolverConfiguration resources in order to process the <AttributeEncoder> elements within it in order to produce a compatible set of rules to use. The default set of rules supplied with the software is not loaded in order to prevent any changes in behavior, including duplication of encoded attributes.
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