mailu/docs
bors[bot] 0839490beb
Merge
2479: Rework the anti-spoofing rule r=mergify[bot] a=nextgens

## What type of PR?

Feature

## What does this PR do?

We shouldn't assume that Mailu is the only MTA allowed to send emails on behalf of the domains it hosts.
We should also ensure that it's non-trivial for email-spoofing of hosted domains to happen

Previously we were preventing any spoofing of the envelope from; Now we are preventing spoofing of both the envelope from and the header from unless some form of authentication passes (is a RELAYHOST, SPF, DKIM, ARC)

### Related issue(s)
- close 

## Prerequisites
Before we can consider review and merge, please make sure the following list is done and checked.
If an entry in not applicable, you can check it or remove it from the list.

- [x] In case of feature or enhancement: documentation updated accordingly
- [x] Unless it's docs or a minor change: add [changelog](https://mailu.io/master/contributors/workflow.html#changelog) entry file.


Co-authored-by: Florent Daigniere <nextgens@freenetproject.org>
..
_templates Restore VERSION_TAG template
assets removing unneeded image
compose Fix a bunch of typos
contributors Add development documentation again
kubernetes/mailu simplify
swarm Fix a bunch of typos
.env Add deploy settings for server
Dockerfile Process code review remarks
antispam.rst Merge
arm_images.rst Fix a bunch of typos
cli.rst Fix small typo in config-import example template
conf.py Set language to English for sphinx in conf.py.
configuration.rst Merge
database.rst Update database.rst
demo.rst Fixed small typo
dns.rst Fix a bunch of typos
docker-compose.yml Make docker-compose.yml for setup and docs development friendly
faq.rst Fix a bunch of typos
features.rst remove service status "feature"
general.rst Update general.rst
index.rst Add anti-spoofing to the feature list
maintain.rst Documentation:
nginx.conf Build the documentation as a Docker image
releases.rst Fix a bunch of typos
requirements.txt Added missing extension in conf.py. Added missing library in requirements.txt. Sphinx is only compatible with docutils<0.17
reverse.rst Fixed error in reverse.rst and remove unneeded example block.
setup.rst Merge branch 'master' into feat-switch-buildx
webadministration.rst Fix a bunch of typos