I have found that Norton 360 for Mac Vulnerability Protection (on Big Sur 11.2.3) is interfering with using Sidecar via a wire. If I turn on Vulnerability Protection, Sidecar shows only a black screen on my iPad. If I turn off Vulnerability Protection, then the Sidecar display is fine. I have extensively tested this issue by erasing the hard drive and reinstalling apps one by one (multiple times) to diagnose the problem, and this is definitely it. However, I can't figure out which specific setting in Vulnerability Protection is the problem (without disabling it entirely) to allow Sidecar to work correctly. I have tried excluding all local network addresses from Vulnerability Protection, but still have the problem. Any thoughts?
As you answered, the problem was not solved in ver8.6.3 updated on 4/30. I asked the support chat about this. Support staff acknowledged that similar problems were occurring elsewhere. It's very annoying, but I hope the next update will fix the problem. I asked the support staff to get an email notification when it was updated. Until then I decided to remove Norton and install ESET. ESET does not cause any problems when SIDECAR is connected via USB.
If there was an update, it hasn't solved this problem.
Hi, I have the same issue, so I asked Norton Support. They say this issue will be fixed in the next version, which will be released on April 30th, 2021.
Until then, it's frustrating, but I have no choice but to use sidecar with wifi.
Best wishes.