Virtualmin plugin for keeping notes
This is a Virtualmin plugin (which is a Webmin module with some meta data and methods to integrate it with Virtualmin) that provides a simple UI for leaving notes on the dashboard for yourself or other administrators. It's also probably a pretty good "first plugin" to look at because it does almost nothing, and ties into the virtualmin UI.
If you just want to use it, install it from the Virtualmin softare repositories:
CentOS/RHEL/Fedora/yum/dnf
# yum install wbm-virtualmin-notesDebian/Ubuntu/apt
# apt-get update; apt-get install webmin-virtualmin-notesOthers, grab the .wbm from https://software.virtualmin.com/gpl/wbm and install it using the Webmin Modules module.