prefers-color-scheme 'dark' on Firefox
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Wed Jan 19 23:37:28 EST 2022

The prefers-color-scheme media query [1] has become the de-facto
way of auto selecting a darker theme on many sites. The only
problem is that it _seems_ that Firefox takes its hints from the
underlying desktop environment, and I usually run window managers
without this magical attribute set.

I found this about:config variable a while back to trick firefox
into thinking I'm using a dark "system theme", which works great,
but I always forget it (it can't be versioned in my dotfiles!), so
here it is in my gopher notes:

1. Go to about:config
2. Add a new property with the name:

	ui.systemUsesDarkTheme

3. Set the value to "Number" and "1". No booleans allowed!

[1]: https://developer.mozilla.org/en-US/docs/Web/CSS/@media/prefers-color-scheme