Extension:UserMerge

User Merge and Delete extension allows wiki users with the usermerge permission (Bureaucrat by default) to merge one Wiki user's account with another Wiki user's account.

The extension allows to Limitations Extras
 * merge (refer contributions, texts, watchlists) of a first account A to a second account B
 * delete the first account A after the merge (option box)
 * you cannot delete a user A without having merged the user A to B
 * you cannot merge your own account (logged-in user)
 * if you omit the "New User" field, then the extension auto-populates the New User as "Anonymous" (user_id 0), and ask you to confirm a merge to Anonymous. This is used for user deletion: you first empty (merge to user 0) contributions of a user A, and then delete the user A.
 * the extension creates a User Merge log and logs all User Merge extension activity.

Usage

 * follow Installation Instructions
 * a new Special Page Special:UserMerge with the title Merge and Delete Users is created
 * unmergeable users can be defined (examples):

Known issues

 * It's not possible to merge the account of a blocked user (cf. bug 39470)
 * The extension lacks an API interface module (bug 39636)