The site notice can be set by admins of a wiki by editing the page MediaWiki:Sitenotice. This shows as a message at the bottom-left of all pages and is useful for notifying the whole community of a wiki of news or a discussion.
Once a contributor has read the notice, they may prefer not to view it any more. If they have cookies enabled, they can dismiss the notice using the "dismiss" link next to the text. This will work whether they are logged in or not. As long as they don't clear the cookie, the notice will remain hidden.
To reset the notice and make it visible again to everyone (for example, when an admin has put up a new notice), the number in MediaWiki:Sitenotice id needs to be increased by one. If this page doesn't yet exist, it can be created with a starting number of 0. The new notice can be dismissed after reading in the same way as the last.
To clear the message, MediaWiki:Sitenotice should be reset to the default: -
- Use a site notice for important updates or temporary messages only. If site notices are used too often, regular users to your wiki might begin to ignore them, which makes it harder to get the really important notices out. When the notice is not needed, clear the message as mentioned above.
- Keep site notices short and sweet — one or two lines of text works best when paired with links to more extensive information.
- Keep page load times fast by avoiding images, DPL, or other extensions in the site notice.
- Consider whether to use MediaWiki:Anonnotice instead, which only shows to users that are not logged in, to show a different message to that group. If both Sitenotice and Anonnotice are set and the reader is not logged in, Anonnotice will take priority. Changing the contents of MediaWiki:Anonnotice does not require incrementing MediaWiki:Sitenotice_id.
- Use the main page, Community Page, or navigation for links to news, policies, or help.
- Sitenotice messages generally should not be signed.
- Announcements, which appear for users in the notifications area across the site
- Sitenotice manual on Mediawiki.org