What's wrong with this entry?
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The /output-style command has been deprecated. It now shows a message directing users to /config or the settings file. The command is hidden from help output but still works for backwards compatibility.
Evidence
Deprecation handler (search for "/output-style has been deprecated", "Deprecated: use /config to change output style")
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
Related
Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.