Though the benefits are obvious, the one clear drawback observed is that the webpages got darken also LOAD LONGER; and even when it seems it's done, the load button still show X sign, which indicates it's still loading.

Particularly occurs in search websites and websites which already have dark theme in them.

Hence, what's supposed to be an energy-saving extension turns out doing the opposite to my PC.

This behavior appears both in both my Firefox and Chrome browsers.