Merge #2336

2336: helm-chart is now in sync; update the wording r=mergify[bot] a=nextgens

## What type of PR?

documentation

## What does this PR do?

Don't mislead users into setting up 1.8 if they use k8s; There is no reason to anymore.

### Related issue(s)
- #2333
- closes #2316


Co-authored-by: Florent Daigniere <nextgens@freenetproject.org>

CHANGELOG.md

@@ -3,10 +3,7 @@ Changelog
 
 For full details see the [releases page](https://mailu.io/1.9/releases.html)
 
-Warning, the helm-chart repo is not in sync yet with the new Mailu 1.9 release. If you use helm-chart (kubernetes), we advise to stick to version 1.8. 
-
-Upgrade should run fine as long as you generate a new compose or stack
-configuration and upgrade your mailu.env.
+Upgrade should run fine as long as you generate a new compose or stack configuration and upgrade your mailu.env. Please note that once you have upgraded to 1.9 you won't be able to roll-back to earlier versions without resetting user passwords.
 
 If you use a reverse proxy in front of Mailu, it is vital to configure the newly introduced env variables REAL_IP_HEADER and REAL_IP_FROM.
 These settings tell Mailu that the HTTP header with the remote client IP address from the reverse proxy can be trusted.

docs/maintain.rst

@@ -15,6 +15,7 @@ simply pull the latest images and recreate the containers :
 .. code-block:: bash
 
   docker-compose pull
+  docker-compose down
   docker-compose up -d
 
 Monitoring the mail server

docs/releases.rst

@@ -4,8 +4,8 @@ Release notes
 Mailu 1.9 - 2021-12-29
 ----------------------
 
-Mailu 1.9 is available now. The helm-chart repo is not in sync yet with the new Mailu 1.9 release. If you use helm-chart (kubernetes), we advise to stick to version 1.8 for now. 
-See the section `Upgrading` for important information in regard to upgrading to Mailu 1.9.
+Mailu 1.9 is available now.
+Please see the section `Upgrading` for important information in regard to upgrading to Mailu 1.9.
 
 Highlights
 ````````````````````````````````
@@ -119,7 +119,7 @@ A short summary of the new features:
 Upgrading
 `````````
 
-Upgrade should run fine as long as you generate a new compose or stack configuration and upgrade your mailu.env.
+Upgrade should run fine as long as you generate a new compose or stack configuration and upgrade your mailu.env. Please note that once you have upgraded to 1.9 you won't be able to roll-back to earlier versions without resetting user passwords.
 
 If you use a reverse proxy in front of Mailu, it is vital to configure the newly introduced environment variables `REAL_IP_HEADER`` and `REAL_IP_FROM`.
 These settings tell Mailu that the HTTP header with the remote client IP address from the reverse proxy can be trusted.