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This also implies that if there are no stable MVs for a release, parsing will fail. For example, if 3.8-IV0 is unstable, we will not be able to parse the string "3.8". But we will be able to parse "3.8-IV0" as intended.
Prior to a release, all MetadataVersions for that release must be stable.
Other KIP-584 Features
Similar to MetadataVersion, other KIP-584 features may choose to hide themselves unless unstable.features.enable is set to true. While hidden, they will not be advertised by stable brokers and controllers, or accessible to users.
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