Some of our users want to disable mail from Calendar, but still get mail because one of the projects they belong to is invited to the event. There seems to be no way to avoid receiving mail in this case.

1. Have another user create an event and invite a project that you're a member of.
2. Set all Calendar emails to Ignore in personal email preferences.
3. Let another user accept the invitation.
4. You will receive an email about the other user attending the event.

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arcanist b9e79d14c143afbfb2f29fd26a9a440fb397125c (Sat, Jul 8) (branched from 165df12046e58390f0d00f4cf3e1aa1ab0eb1365 on origin)
phutil 30065f1c5a39f4de8f3b67429d7d68af661f47bb (Sat, Jun 24) (branched from 0a4487d37cd72b3b91ac332377f2b12d4e5a2543 on origin)