The first line must start with [Dd]ocs note:
It may span multiple lines
The Docs note text will be this line and every subsequent line until another section is reached (Release note: or Release justification:) or until the end of the commit description is reached.
The contents will describe why the commit was needed.

TODO:

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What information do I need to put in the Docs note

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?

TODO:

Note that the text does not end up in the documentation. It is used to inform the docs writers and it does not need to be short or concise like folks often do for release notes.