Milestone (M) builds occur throughout the development cycle when a significant set of features or bugs have been implemented. The build will be stable enough for testing those new changes but may have introduced new bugs or instabilities to other parts of the code. Milestones give the community an opportunity to provide feedback on a feature while there is still time to change it during that dev cycle. Milestone builds should never be put into production.
A similar page is available for Stable Builds and Latest Release Candidates.
If there is no Milestones available for the latest version of a package, then the latest RC or stable build will be shown.
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