Stephen Harris

This plug-in will only work on a Multisite running WordPress 3.9+.
This plug-in allows an Network Admin to create admin notices that appear on the top of all admin screens of the 
network’s sites. This notices are styled identically to the “normal” WordPress notices that you might see (WordPress 
updates, “post published” messages etc). Additionally each notice has a “dismiss” link which allows the user to 
instantly dismiss the notice.
Once a user dismisses a notice there will never again see that notice, on any of the network’s site.
Health Warning: The notice messages are considered HTML! A “small” inline tinyMCE editor will be used in a 
future update. But for the time being be aware that when you create/edit notices you are editing HTML (think WordPress 
‘text’ tab on the editor).
Before using the support forums, please read the FAQ. Thank you!

Multisite Admin Notices

Allows a network admin to create admin notices for blog admins.

umangapps

Smart Admin Notice Manager cleans up your WordPress dashboard by grouping admin notices by their source (plugin or theme). 
It prevents notice spam by providing “Remind me later” functionality and allowing you to permanently dismiss notices.
Features: 
* Group by Plugin: Notices are organized into collapsible panels based on the plugin that generated them. 
* Auto-hide Repeated: Identical notices are automatically de-duplicated. 
* Snooze: “Remind me later” button to hide notices for 24 hours. 
* Dismiss: Permanently hide notices.

Toggle Admin Notices

Manages plugin & theme admin notices intelligently.

Multisite Admin Notices vs Toggle Admin Notices