[Feature Request] Darken background when dark style is active

[acly7946]

The default gnome wallpapers have a darker counterpart for when the system dark mode is active:

I typically use dark mode in dimly lit environments, and some wallpapers can be unpleasantly bright.

I would like it if the extension could darken the wallpaper slightly on dark mode. It could be under a toggle switch called 'Dim background with dark style'.