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I've been looking for a way to dial down reddit's white background late at night. I ended up using Control Freak (which is very cool) with my own custom styles. It works perfectly.
Except when it loads a new page it still defaults to white for a couple seconds before loading my custom styles (which show up in "user agent stylesheet" in dev tools)
Is there any way to prevent the screen from flashing bright white, like it does, before the user agent stylesheet is loaded?