Hide or dismiss the WordPress core update notice

Pantheon MU-Plugin 1.5.7 adds dismiss and hide controls for the Pantheon WordPress core update notice ("A new WordPress update is available!"). Apply upstream updates to get this version of the mu-plugin.

Dismiss the notice

Any user who sees the notice can dismiss it with the X in the corner. The dismissal is saved per user, so it persists across page loads and logins. The notice reappears only when a newer WordPress version becomes available.

Hide the notice

To hide the notice more permanently, or for everyone, you can:

• Target #pantheon-update-notice (or the .pantheon-update-notice class) with CSS.
• Return false from the pantheon_show_update_notice filter.
• Define the PANTHEON_SHOW_UPDATE_NOTICE constant as false in wp-config.php.

For details, see Suppress WordPress Admin Notice.