https://github.com/petere/postgresql/commit/11eade9302d0a737a12f193c41160fb895c0bc67.patch
The upstream release notes are here: https://github.com/snowballstem/snowball/blob/v2.2.0/NEWS There are no new user-visible features.
There is another snowball release out, and I have prepared a patch to
integrate it. Since it's quite big and mostly boring, I'm not attaching
it here, but you can see it at
