Responsive Design Mode doesn't offer device sizes

[kotkifotki]

Expected Behavior

When switching to Responsive Design Mode, a list of devices should be available for selection.

Image of an actual behavior of LibreWolf 130.0-3. This been available on the Mullvad Browser prior to 14.0.

Actual Behavior

After switching to Responsive Design Mode, no devices are available for selection.

MullvadBrowserNoResponsiveDevices.webm

Steps to Reproduce

1. Enable Responsive Design Mode (Cmd + Opt + M on macOS or equivalent shortcut on other platforms)
2. Attempt to select a device from the menu

Additional Information

Version: 14.0 (64-bit)
Operating System: macOS 15.1
Architecture: aarch64

Version: 14.0 (64-bit)
Operating System: MX Linux 23 (6.1.0-27)
Architecture: amd64

[kotkifotki]

The issue persists on macOS 15.1.1 with Mullvad Browser version 14.0.3. I am unable to test on MX Linux anymore.

[Thorin-Oakenpants]

https://gitlab.torproject.org/tpo/applications/tor-browser/-/issues/43334