How long have you used it? I go through a few days of placebo effect with every new thing I try and then its back full force. I hope it persists but know I cannot make a judgement until a week or to minimum. I have learned refresh rate is irrelevant to me along with PWM, Blue light and the usual. I don't enjoy looking at a bluish screen for example just based on colors and tint...but it doesnt make strain worse or better either way.
deepflame
Please keep us updated, especially after 3-4 days, as initially hope and a new type of screen can overshadow strain which will build up over time which @hpst suggested too. I've been thinking about gaming gear myself as it should have better screen properties than regular laptop, of course "better" may actually be worse for us 
hpst yeah, the same for me. I also get strain from looking at my DLP projector and all the laptops I have (mostly newer MBPs). For me I think the biggest problem is flickering in any way. So far this is the best screen I have used.
Will keep you posted and update beginning of next week or so.
This is without a doubt the best screen I have used in years. I am so happy with it.
I think the reason is really the refresh rate and some inserted frames that the monitor manufacturers insert to reduce ghosting.
E.g. on my LG monitor I have a setting for "response time" (which should eliminate ghosting) and one for "1ms motion blur reduction". Both add some sort of black intermediate frames that produce flicker.
With 240Hz and these settings to "off" the image is very stable.
I think the refresh rate would also explain why my eyes feel so comfortable with an iPad Pro. As far as I understand it also has a higher refresh rate (up to 120Hz).
I will update you about this in a few days. Need to do my tax declaration. So there will be a lot of sitting in front of the screen now...
Just a test, what happens if you set the "refresh rate" to 60Hz in the graphics settings, does it give you strain?
What OS and graphics card are you using?
Assuming the graphics card can output the refresh rate itself it should be able to do it. FreeSync/G-Sync is for adjusting the refresh rate on the fly to avoid tearing without V-Sync (induces input lag).
Oh I see your on OSX with a MacBook.
Just a thought, might not be accurate, but maybe since the screen is running at a higher refresh rate the dithering is "running" at a faster rate?
If that's the case just wait until I get my dithering fixes done.
KM 240 Hz with any graphics card
Well, you need a graphics card that does 240Hz of course. I think those should be ones that can drive 4k screens at 60 Hz. The screen I have has full HD at 240Hz. That is one quarter the resolution of 4k at four times the refresh rate...
JTL "refresh rate" to 60Hz in the graphics settings, does it give you strain?
Yes, it does. Also the 144Hz that the screen supports. 240Hz is really nice for me.
KM Yes, absolutely. But I still feel a bit discomfort when using Firefox Quantum vs. using Safari. So there is still something going on but the main source of flicker is eliminated.
Hey there, just to give you an update. I have used this screen intensively for 6 days in a row now with 6-7 hours straight pretty much every day. I have to say that I have quite some headache now. Not sure if this is the screen, dry eyes or simply stress because I had to finish my task on time.
Will investigate further and update.
KM Have you ever come across this website in your research before?
MagnuM No, but I definitely get motion sick when playing 3D games where you move quickly and the path is narrow. Or when I watch related videos. The more open the field, the better it gets.
Edit: To clarify, my quoted comment was not related to this. The question I asked was to understand if 144 Hz may help with eye strain you get when you look at static screen content (e.g. Windows 10, Firefox Quantum, some Android versions...).
deepflame I expected as much since it takes a few days for most new stuff to really show you if it's going to be ok long term. I didn't think refresh rate should help based on personal experience and the way LCD's refresh, but it was worth a shot. Whatever the root cause is for you is still happening.
hpst Did you find a setup that is working for you for long periods of work in front of a screen yet?
I have to say that I was diagnosed with nystagmus (uncontrolled eye movement/flickering) and thought that my condition might have to do with that as well. However I can remember that I had streaks of long working hours years ago like most of you had. Or maybe I just get old(er), not sure
deepflame I have some weird eye stuff as well but it's proven not the root cause of my problem. I wouldn't argue it can make things worse...but there is definitely a technology issue at play here for 99% of people in my opinion as proven by the fact everyone has at least one "safe" thing they can look at...and we don't have the same strains in non screen related life.
JTL I've had nystagmus
so you mean it is gone now with your "special treatment"?