Sometimes when isolating a group (double clicking) and zooming in, a strange ghost offset projection across all the screen appears, and it slides across the screen when dragging through the workspace.
I remember it used to happen in Ai 2019, stopped happening in Ai 2020 and now it came back. BUT I have not had this issue occurred between the Ai 2021 release and the macOS Big Sur update so I am not sure what the cause could be, and that's what's tricky, it only happens SOMETIMES and I haven't found any pattern about it.