Dismiss “Core Update” nag on dashboard, “Indicators” on admin menu, admin bar or toolbar, dismiss “Maintenance Mode”, when it is activated, or automatically, if it is in mu-plugins directory.
Tips
A neat trick, is to put this single file dismiss-update-nag.php (not it’s parent directory) in the /wp-content/mu-plugins/ directory (create it if not exists) so you won’t even have to enable it, and will be loaded by default, also, since first step installation of WordPress setup!
About it
The code of this plugin, is not written with a php framework, but with a simple php editor, manually, compatible UTF-8 without BOM, and Unix LF. To avoid code corruption, do not edit it with WordPress embedded editor, or with any specifications incompatible editor.
Translation
Translated by: Luciano Croce
Acknowledgements
Thanks to Andrea Gandino (andg) for Italian translation approval.
Thanks to Garrett Hyder for English (Canada) translation approval.