[hoosieree]

When your pupils are smaller, the image that hits your retina is sharper, just like with a pinhole camera.

Sharper images lead to less eyestrain because you don't need to keep your eye still for as long.

I use light color themes for this reason. Although I always add the caveat to "do what works for you", because everyone's body is different.

[alanbernstein]

As a dark mode user, this makes me want to reconsider. It seems to make sense, but is it supported by evidence or by personal experience? I have not noticed such a difference in eye strain myself.

[pepa65]

The strain on my eyes is majorly caused by the lights shining into it. Dark mode helps, lower light emission helps. My eyes don't seem to strain so much keeping still...