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This is for use on pages documenting the next (prerelease) version of Blender. Note that the page names do not have the Blender version number in them, only a generic suffix like “New”. This is to allow the pages to be reused: when the prerelease version becomes the release version, the content can be moved from the “New” pages to the regular pages; and then the “New” pages can now hold the content for the next prerelease version, with no need to move pages.

The actual page content, of course, can reference specific Blender version numbers, and be updated accordingly.