Can I turn off email notifications?
If you'd like to stop receiving notifications for a single issue, you can unfollow that issue. If you are the opener or assignee, you'll need to select another team member first, but after that, you'll stop receiving notifications for that issue unless you comment on it in the future.
If you'd like to turn off all notifications for your user account, just go to "Profile" and scroll down to "My Notifications". You can opt-out of email notifications and, if you'd like, select a daily summary as a less chatty alternative.