I have several Rpi3Bs and for the most part they work well.
But one of them insists on changing the USB keyboard type to the UK keyboard.
I fix it after a reboot by going into Menu..Preferences..Keyboard..Keyboard and Mouse..Keyboard Layout
It would me nice if I could figure out where this setting is stored and mark the file read-only or something. The one thing I have figured out is that it is not set in /boot/config.txt
In Raspi-config, localization is set for both gb and en_US - not sure why.
So the question is in the title: How can I force Raspbian stay set to the US keyboard?