Your feedback is much appreciated. The requirement for a user to be enrolled in order to appear in the Merge list has proven confusing, as has the naming of the Merge feature (as opposed to e.g. Delete), but the underlying cause of the problem is the fact that the user database is shared between journals, which is a design choice that has actually served us very well.
We've considered a few approaches, such as moving the Merge function into the Site Administrator's role and listing all users rather than only enrolled users, but nothing has been implemented yet.
I've asked the author of the OJS in an Hour document to review this thread and take your suggestions into account for the next release of the document.
Public Knowledge Project Team
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