With our notification scheme when an issue gets commented, "All Watchers" and "Current Assignee" both get notified. The Reporter is not listed in the Issue Commented.
Then a user (User X) reports an issue, selects to watch it, and the issue is being worked and then gets a comment added to it by another developer.
User X does NOT receive any notification for that comment.
Is it possible that because user X is both a reporter and a watcher, that is why this User X doesn't receive any notification?
X should get an email for any comment. It doesn't matter if X is the reporter and the watcher, the rule you have is "watchers get mail". (Exception - check their profile, there's a flag to say "don't mail me on my own changes", so if X comments, X won't get a mail, although all the other watchers and assignee will)
The other developer's comment should definitely have mailed X. Twice in fact, as you have Reporter and Watcher set to get the mail, but JIRA de-duplicates this and only sends one.
Could you test it with other users?
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