[jwmoz]

Yep I used to get them too, sore eyes also and weird squinting. I run my screen at about 2/3 or 3/4 brightness, I use a dark theme in my IDE and I also always bump up the font size. Doing all this I don't get headaches or eye squinting anymore.

Also I use flux and try not to use the computer much at weekends.

[jotato]

I always increase font size. Either I am getting old, or font sizes are way to small in most places.