Support for OS dark mode toggle

[Dave-Snigier]

WIth MacOS, IOS, and Android support for dark mode and the prefers-color-scheme CSS media query, it would be great if this script would respect those settings if set.

The behavior I was thinking is:
prefers-color-scheme == light --> Disable dark mode related styling, but keep other tweaks enabled
prefers-color-scheme == dark --> Enable dark mode related styling
prefers-color-scheme == false (unset) --> Enable dark mode related styling

Ideally, there would be a feature toggle which could override the OS setting.

Mozilla - prefers-color-scheme
prefers-color-scheme: Hello darkness, my old friend

Thoughts? Thanks for the great project!

[the-j0k3r]

I have a userCSS for this, its a work in progress and will be posted in https://github.com/StylishThemes/Feature-Override-Styles

Also for better user experience I recommend stylus + github dark and not github dark script, the latter doesnt support multiple @moz-doc sections and its needed.