I have a Sony laptop with a touch screen and windows 10 running Firefox 53.03. Firefox's about:config detects the following preference: ui.osk.debug.keyboardDisplayReason userset string IKPOS: Keyboard presence confirmed. I want to override it to be: ui.osk.debug.keyboardDisplayReason userset string IKPOS: Touch screen not found. I have tried creating a user.js with the following content: user_pref("ui.osk.debug.keyboardDisplayReason", "IKPOS: Touch screen not found."); but about:config does not change. If I go into the device manager and disable the touchscreen, then I get the correct preference and Firefox works correctly, but I'd like to keep the touchscreen enabled. Thanks. Zig