The release notes can be found here:
Under the OpenNMS 19 section there is this paragraph:
Release 19.0.0 is the latest stable release of OpenNMS. It contains a large number of bug fixes and new features, most notably support for all major OpenNMS polling and collection features in the Minion. For a high-level overview of what’s changed in OpenNMS 19, see What’s New in OpenNMS 19.
Where the last phrase is a hyperlink to:
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