hello,
i tried changing the resolution on my fire hd 10 (2021) with
adb shell wm size 1280x800
adb shell wm density 600
adb reboot
after reboot it defaults to portrait mode and i can only see the default wallpaper. nothing happens when i touch the screen. if i tilt it to landscape it disappears. if i hold power button a large grey box moving up and down appears, with 3 options to power off, restart, and lockdown. i cant authorize debugging to use firebox.
i think i should have set density to 150? i just followed someone's instructions.
also, it had already auto updated fireOS when i did this.