iPad Air 5th Gen, iPen 2, Control by Pen Pressure Requires the Use of a Pressure Sensitive Tablet

Thank you for your suggestion. I did use that reference to set my Sidecar configuration, but I set it to Mirror Built-in Retina Display.

So this time I set the Sidecar configuration to Use as Separate Display, and I dragged the Photoshop UI into the iPad display.

Now, I get the correct behavior with the brushes and pen pressure.

If I change the Sidecar setting back to Mirror, the brushes' pen pressure continue to work.

Now I shutdown Photoshop, and try to reproduce the entire test. The brush pen pressure stops working, and I see the warning about the pressure sensitive tablet requirement.

I return the Photoshop UI back to the Mac. I close the brush windows. I turn off the Sidecar setting to my iPad.

I turn it back on. It works again.

I conduct another test.

This time, I leave the brush windows open. I close Photoshop. The brush selections and the brush settings windows are open. I start Photoshop. I move the UI to the iPad. Problem returns.

I disconnect my iPad from Sidecar. I reconnect. I drag the Photoshop UI to the iPad display. It works.

I will use the disconnect/reconnect iPad technique and see if this resolves the issue. Also, I'll close the brush windows if they are open before I shutdown Photoshop.