eisenivan

A lightweight plugin that allows you to place a sitewide alert message in the header of your site. There are options to include a default set of styles (based on Twitter Bootstrap), center your alert, and switch the style class.

Summits Alert

A lightweight plugin that allows you to place a sitewide alert message in the header of your site.

Tomas

Plugin Name: Announcements
👉 <a href="https://tooltips.org/product/announcements/" rel="nofollow ugc">Free Download</a> | <a href="https://tooltips.org/wordpress-tooltip-plugin/announcements/" rel="nofollow ugc">Announcements Document</a> | <a href="https://tooltips.org/contact-us/" rel="nofollow ugc">404s Support</a>| <a href="https://tooltips.org/forums" rel="nofollow ugc">Support Forums</a>
Announcements is a simple & easy-to-use solution that help you to show / edit / add / delete announcements in your admin area, if user logged in your admin area, they will see all announcements first, 
if logged in users do not accept your announcements, they can not open any menu or links in your wordpress back end, the only page they can view is your announcements in back end. This plugin can help you show TOS or Notes for any users when they logged in your back end
In Announcements setting panel, you will add title, message in Announcement Message Editor, also there are options that allow users view an announcement and do not need to access the agreement, and still can open admin menu or links, all these announcements will be stored 
in Announcements menu, if users open announcements menu, they will find any messages / notes you sent to them.
Announcements setting panel, you can add / edit / delete any announcements very easy.
More amazing features are being developed and any feature request is welcome.
Feature request & Support URI: https://tooltips.org/forums 
<h3>Download</h3>
https://wordpress.org/extend/plugins/announcements/

Announcements

When users logged in admin area, they will see announcements first,  if users  did not accept announcements, they can not open any menu in back end.

Summits Alert vs Announcements