FaceTime bug fix removes the 'Add Person' feature for one-to-one callsLearn all about the latest updates, changes, and fixes to FaceTime due to the Group call security bug fix.
A serious FaceTime Group Call bug was discovered that lets you instantly access audio from the microphone and potentially the video of the person you called on FaceTime. The bug was fixed, but new issues have arisen in its place.
Update: February 18, 2019: FaceTime bug fix removes the 'Add Person' feature for one-to-one calls
Apple pushed out iOS 12.1.4 recently to fix the security bug with Group FaceTime. The fix, it appears, is in part, to keep the "Add Person" feature disabled for FaceTime calls that start out as one-to-one calls. As discovered by MacRumors forum members, when starting a FaceTime call with a single person, you can't add a person to that call.
Though some FaceTime users also reported not being able to add a second person, even during a call that started as a Group call, I was able to successfully start a Group call with two others, and add a fourth person.
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FaceTime bug fix removes the 'Add Person' feature for one-to-one calls