In package pages like [1], there is a link to "Debian Patch Tracker". Trying to access it, however, says that the "patch-tracker.debian.org" domain does not exist.
[1]: https://packages.debian.org/sid/samba [2]: http://patch-tracker.debian.org/package/samba/2:4.1.17+dfsg-2 -- Mantas Mikulėnas <graw...@gmail.com>