With this information, I'm going to ask Apple what I need to do with this. It's definitely a system bug or flaw, which needs to be addressed by a system update. I expected that it might be possible to 'kick' the system's display sensing routine, but SwitchResX's developer Stépahne Madrau investigated the issue last week, and said this isn't something a user can fix with available tools or user-friendly hacks. The only solution is to completely Restart.īelow two samples of a settings panel in SwitchResX: Even the most drastic Rotate setting doesn't do the trick.

Using the plain Display Preference panel (or with special option-invoked settings) won't work. So the system is strangely still aware of the recently connected projector with a certain resolution, while the LG is also detected but getting the signal and resolution of the assumed other external display. The SwitchResX tool helped me discover that in such an instance, there are in fact THREE displays (falsely) being detected: the MacBook's built-in, an earlier connected display like a projector or presentation screen, and the physically connected LG, showing up as a 'ghost' display. My LG is also detected but at the resolution of the former ! once in 3 to 4 times, the system still thinks the earlier display is still connected. I deliver a lot of presentations and courses, connecting various projectors and screens to my MacBook. I have the same issue, and in fact with the exact same configuration BlkPengu has: a MacBook Pro 16' (2019) and an LG 34' widescreen.

Macbook restart shortcut