Hi, dark mode is available only in new Firefox Preview for Android:

https://play.google.com/store/apps/details?id=org.mozilla.fenix

Actually i wanted to get dark mode in mozilla firefox main browser

Hi

In Firefox for Desktop, if you change the theme to a dark theme, websites configured to supply a dark theme should use it. This article will help:

https://support.mozilla.org/en-US/kb/use-themes-change-look-of-firefox

Hi

you can get dark mode in Mozilla Firefox Android by following these steps.

Open the Firefox browser and click the open menu button on the right side corner.(boxed in blue) Then click customize. Then click on the themes button at the bottom corner and select the dark mode. Finally click on the done button in the right corner.