- In betalabs, on wikitext page, mention a non-existent user.
- If 'Failed mention ' option is enabled, the user who wrote the mention receives "Your mention was not sent..." notificaitons.
- Correct the user name and delete the signature and re-enter the new signature (i.e. ~~~~)
- The Mention notification will not be sent - not a failure/success not an actual Mention notification to a user that was mention.