Postfix stable release 3.7.0

[An on-line version of this announcement will be available at https://www.postfix.org/announcements/postfix-3.7.0.html]

Postfix stable release 3.7.0 is available. This ends the support for legacy release Postfix 3.3.

The main changes are below. See the RELEASE_NOTES file for further details.

You can find the updated Postfix source code at the mirrors listed at https://www.postfix.org/.