Datasheet

isn't being picked up:

Check /usr/share/X11/xorg.conf.d for a file called 10-evdev.conf

If you don't see that file

1. You need to sudo apt-get install xserver-xorg-input-evdev , and then...

2. If you do have a 40-libinput.conf in that same directory, you must remove it even if/once evdev is installed,

since it will override the 10-evdev.conf otherwise.

Thanks to cerebrate in the forums for the hint!

https://learn.adafruit.com/adafruit-pitft-28-inch-resistive-touchscreen-display-raspberry-

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