Can't disable touchpad while typing

I want to disable the touchpad while typing, but can't seem to do it. The gnome setting is set to true, but it does nothing.

$ gsettings get org.gnome.desktop.peripherals.touchpad disable-while-typing
true

$ cat /proc/bus/input/devices | grep -i touchpad
N: Name="ELAN1201:00 0 4F3:3098 Touchpad"

For me, this was caused by the touchpad/keyboard being incorrectly registered as external devices. The disabling when typing behaviour is only for internal input devices.

To fix it I did the following:

Make sure libinput-tools is installed, sudo apt install libinput-tools

Then sudo libinput list-devices

This gives you a list of devices from libinput, such as keyboards and touchpads

You'll want to take note of the Kernel item for your keyboard and touchpad. It may be a bit tricky to figure out which ones you need, I had 2 entries for my keyboard, an entry for my touchpad, and an entry for mouse, while not having a mouse plugged in.

Then for each of the Kernel paths, run the following

sudo libinput quirks list /dev/input/event7 (replacing the path)

Take note of the devices where this command DOES NOT output AttrKeyboardIntegration=internal. If all devices output this, this solution will not work.

Finally, create a file /etc/libinput/local-overrides.quirks

[Name of overwrite, doesn't matter much]
MatchUdevType=keyboard
MatchName=NAME OF DEVICE
AttrKeyboardIntegration=internal

Where MatchName is equal to the Device item of sudo libinput list-devices

MatchUdevType should be the type of device. keyboard, touchpad & mouse did the trick for me.

Add a separate entry for each device that did not output AttrKeyboardIntegration=internal previously