In Nightly 54, we’ve just landed support for custom devices in Responsive Design Mode.
Each device can have its own:
- size
- devicePixelRatio
- user agent
- touch support
Also, you can preview the properties of existing devices by hovering over the name in the device modal where they will display in a tooltip.
@miketaylr and @DenSchub, should be useful for the Web Compat team as well!