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The result of this is that upgrading from one minor version to another does not require any change other than installing the version to be used and updating the builds of any third-party plugins used. Existing configuration files will work unchanged, but may need to be modified to take advantage of new features. Downgrading to an older minor version may require removing configuration options introduced in newer versions.
Note that in adding APIs, abstract or interface methods are not added to existing public interfaces or classes to guarantee compile-time compatibility of for existing extensions.
Major Version Compatibility
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