Camera App Missing!!
The Camera app on my Macbook is suddenly gone, and none of my apps that require it recognize any camera at all. There definitely is a built-in camera, I've used it before. Photobooth, FaceTime, Photos--nothing's working and the actual app for my camera doesn't show up anywhere on my mac--not in System Preferences, Utilities, Dashboard, etc. I've tried rebooting, resetting my SMC, and I've followed every instruction from this website: https://osxdaily.com/2013/12/27/fix-there-is-no-connected-camera-error-mac/, but got "no matching processes were found" every time. Please help.
MacBook Air 13″, macOS 10.13