It saves my eyesight.

The best!

Very Good for someone with Insomnia & Seasonal Depression, keeps my rhythms in order.

Its Mozilla addons description page claims it "doesn't show ads" but when you go to its options page, it is absolutely slathered with advertisements for "sponsors" (i.e., the developer has been paid money by these sponsors to put this advertisement there). Extremely dishonest.

the dark theme can protect eyes efficiently,and I don't find a greater theme addon yet.

Неплохо но замедляет скорость обновления страниц в Firefox как на ПК так и со смартфона, это минус.

It works every time

It works well on majority of websites. But sometimes images on some websites don't blend in with the darker tone and creates a bad experience