User:MediaWiki default
This is the username used by the maintenance script rebuildmessages.php. The script is part of MediaWiki; it updates MediaWiki interface messages to be equal to the MediaWiki default. It is not a bot and is unaffected by blocks.
The script has two modes of operation:
rebuildMessages.php --update- Updates any messages which were last edited by "MediaWiki default" to their current version. Creates any messages which did not exist.
rebuildMessages.php --rebuild- Updates all messages to their current default value, regardless of whether they have been manually edited. This is sometimes used on other wikis when a new messages file has just been created, with a comprehensive set of default messages. It has never been used on the English Wikipedia.
If the MediaWiki default account name does not exist, edits made by this script have a user ID of zero so they are treated as anonymous edits in the page history, with a link to the user contributions instead of the user page.
The same username is also used by the MediaWiki installer. Installing MediaWiki has the same effect as rebuildMessages.php --update.
If there is a problem with the text of the default messages, please file a bug report at https://phabricator.wikimedia.org. Requests to start or stop the script should be made to the #wikimedia-techconnect channel on irc.libera.chat.