For a while there was an issue causing certain email notifications not to go out.
These emails included specifically private message notifications, thread subscription notifications, and a few others.
The issue has been resolved. Some of you may get a few (or many) notifications coming in over the next few hours as the system is now processing the emails that weren't sent.
Sorry for the inconvenience to anyone effected by this. Email notifications should be going out again as normal now.
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