SendGrid, the service used to send emails from the site, is discontinuing their free plan in the near future.
Rather than just find a substitute (or use their paid service), I've opted to go for a self-hosted solution here. I've tested this and all appears to be working, however please note that as a result of this change, emails from the site may have a higher risk of going to Spam and/or being flagged as "unusual" for a little while.
To the users who previously raised concerns about not receiving all site emails: Has this remained the case even after the change from SendGrid to an internal service?