Header Content module for Phoenix and previous CE versions.
It has been complete new written for BS4 and BS3
Easiest install: upload 2 files+language file.
Install content header module in Admin.
Message Header and Text can be introduced for each language in the content module set-up.
Selectable pages where to show the modue.
This add-on is based on the idea of the older Holiday Message Add-Ons by fimble:
http://addons.oscommerce.com/info/7648
http://addons.oscommerce.com/info/6127