Continuing the discussion from COMPLAINT - latest EDGE- firmware [Edge_Pie_V191205]:
It is actually in the source code to build Android.
So will have to rebuilt firmware with it.
My firmware has the change added but it’s AndroidTV layout not AOSP, phone layout, so other launchers might not work.
You can check if this app has the same problem, running sideways, it’s fixed in my firmware.
https://apkpure.com/apkpure-app.html?icn=aegon&ici=image_home
But I think my patch might cause problems for Khadas’s portable screen that needs rotation.
Here is my latest AndroidTV firmware. Can only use Google Launcher but all apps run landscape.
You can also try this older firmware of mine, it has the same layout as Khadas firmware, but it doesn’t contain the latest changes. But apps should run landscape correctly.
There is also an easier way if you just want to change the DPI from 280 to 240.
Root Android with Magisk and then issue in an Android terminal app a command to change the DPI.
Maybe something like
setprop ro.sf.lcd_density=240 or setprop ro.sf.lcd_density 240
Maybe you don’t even need to be rooted.
I think in Developer Settings there is also a setting to change the DPI, I will search for it.
Tap 7 times on build info in the About screen to activate the Developer Settings.