The dimmer.el library by Neil Okamoto can be configured to automatically dim the colors of inactive Emacs windows. To guarantee consistent results with the Modus themes, we suggest some tweaks to the default styles, such as in this minimal setup:
(use-package dimmer :config (setq dimmer-fraction 0.3) (setq dimmer-adjustment-mode :foreground) (setq dimmer-use-colorspace :rgb) (dimmer-mode 1))
Of the above, we strongly recommend the RGB color space because it is the one that remains faithful to the hueness of the colors used by the themes. Whereas the default CIELAB space has a tendency to distort colors in addition to applying the dim effect, which can be somewhat disorienting.
The value of the dimmer-fraction has been selected empirically. Users
might prefer to tweak it further (increasing it makes the dim effect
more pronounced).
Changing the dimmer-adjustment-mode is a matter of preference. Though
because the Modus themes use black and white as their base colors, any
other value for that variable will turn the main background gray. This
inadvertently leads to the opposite of the intended utility of this
package: it draws too much attention to unfocused windows.