I personally would not use this if it was available. My solution to avoiding eyestrain was to use [redshift.] 1 This put me in control of what I was subjecting my eyes to and had the added benefits of

A) Virtually immediate gratification for me

&

B) Zero effort required by the site developers for something that as mentioned would appeal to a small subset of users.

There are a number of [alternatives] 2 available. You might prefer [blueshift.] 3

I personally would not use this if it was available. My solution to avoiding eyestrain was to use [redshift.] 1 This put me in control of what I was subjecting my eyes to and had the added benefits of

A) Virtually immediate gratification for me

&

B) Zero effort required by the site developers for something that as mentioned would appeal to a small subset of users.

There are a number of [alternatives] 2 available. Due to your preference for darker screens You might prefer blueshift, but currently that one is only available for arch linux. However if compiling from source is not a concern for you the github is located here.