diff --git a/19.1--Installation-using-egroupware-docker-RPM-DEB-package.md b/19.1--Installation-using-egroupware-docker-RPM-DEB-package.md
index 996012d..2b0c780 100644
--- a/19.1--Installation-using-egroupware-docker-RPM-DEB-package.md
+++ b/19.1--Installation-using-egroupware-docker-RPM-DEB-package.md
@@ -51,12 +51,12 @@ As EGroupware is running in a container, it's localhost is not the same as the h
 > To do so go to http(s)://your.host-or-ip/egroupware/setup/ and use the upper login box with the credentials from /var/lib/egroupware/egroupware-docker-install.log. 
 > Then click on [Edit current configuration] and change the LDAP host to 172.17.0.1 
 
-## How to install third party or deprecated apps
+## How to install third party or deprecated apps or update from before 14.3
 The following apps, which are deprecated since 14.3, are no longer part of 19.1:
 1. egroupware-epl-wiki
 1. egroupware-epl-sitemgr
 1. egroupware-epl-phpbrain
-1. egroupware-epl-compat
+1. egroupware-epl-compat (required for update from before EGroupware 14.3!)
 1. egroupware-epl-groups ([Group administration for long term CE users](https://github.com/EGroupware/egroupware/wiki/Group-administration-for-long-time-CE-users))
 
 They can however be installed from 17.1 repo or are kept in case of an update.