[Solved] ... Dual Screen Issues - Monterey 12.2.1

Anybody having any issues with a dual screen display on Monterey 12.2.1?

Clean install with OC 0.7.6 - can't drag mouse across to second screen - Dock and System Prefs are now on second screen and out of reach of the mouse.

System:
Asus Z370-A as in build below (300 Series-1)
Dual PA248 24" monitors connected via HDMI TESmart 4K 60Hz KVM switch

This dual monitor display and KVM switch works fine on Catalina (OC 0.7.0) and Big Sur (OC 0.7.6), just not on Monterey 12.2.1.

EDIT:
1. Some Googling indicates that there are known problems using dual screens with Monterey 12.X
2. To avoid the problems mentioned above, the displays need to be set as "Mirrored," not "Extended"
3. Hopefully, this will be fixed in a future Monterey update.

Any other thoughts will be appreciated.

Have you tied moving the mouse in the opposite direction it would normally travel, to see if the screens are in reversed positions.

If you can open System Preferences and the Displays pane, go to the Arrangement tab. You should see something like this.

Naturally aligned screens.

The white bar across the top of the left hand display icon indicates the screen with the Dock, the main screen. The other screen is normally the second screen, where the System Preferences pane only appears when the Displays pane is selected.

With my dual screens in this orientation I can move the mouse cursor across from one screen, passing across the bezels between the screens from left to right and right to left.

Below is an example where the screens are reverse aligned.

Reversed screens.

In this setup I have to move the mouse cursor to the extreme right edge on the display with the Dock icon, or the extreme left edge of the second screen, for the mouse cursor to move from screen to screen.

The screen arrangement tab allows you to move the two screens in relation to each other, so you may need to drag and position your screens so the mouse moves across like in the first screenshot.

Misalinged screens.

Just make sure you line up the top and bottom edges, otherwise your mouse won't transition across from screen to screen in a horizontal movement.

Edhawk said:

Have you tied moving the mouse in the opposite direction it would normally travel, to see if the screens are in reversed positions.

Click to expand...

Thanks for the tip - a little weird although anything that allows the screens to function in Extended Display is worth it.

Similarly, it appears that windows must also be dragged in the opposite direction to get them on the other screen.

Let's see what happens in future Monterey updates.

Thanks again!

@Edhawk is correct - switching the Primary (Dock) screen and Secondary screen in Display Settings (Extended Display) solved this issue and makes it possible to "move the mouse cursor across from one screen, passing across the bezels between the screens from left to right and right to left."

However, once the issued is "fixed" it seems to be possible to reverse the screens (Dock screen on the right) - see screenshot below - and retain the normal mouses gestures:



Short of reinstalling Monterey to simulate the original problem where the screens were initially reversed, it's difficult to test this, although that is the working hypothesis (as Sherlock would say).