Under the Appearance header, tap Dark to enable this mode.
You can turn on dark mode on your iPhone or iPad by opening the Settings app and scrolling down until you find Display & Brightness.
How to turn on Firefox dark mode on an iPhone or iPad Then, open your Firefox browser, which will display in dark mode. Click 'Colors' and choose Dark as your default mode option. Under Custom, you can either choose to enable this mode under Choose your default Windows mode or Choose your default app mode or both, depending on your preference. Turn on dark mode by clicking the relevant option.
