This came up on the Hadoop JIRA lately. Someone submitted an issue several years ago and the team is investigating it now and he was trying to figure out how to get off the notification list. They ended up having to change the reporter. jfc jira's a mess.
One such 'feature request' is 'unsubscribe from email': https://community.atlassian.com/t5/Jira-questions/How-can-us...
Mental.
I have a rule to send it all to spam.