I've moaned a few times.
https://forkingmad.blog/dark-web-sites/

You should try the Dark Reader plugin

Despite the name, you can compel it to make sites light.

Dark Reader — dark theme for every website

Enable dark mode (night mode) on all websites

Dark Reader (darkreader.org)

And not just dark mode/light mode. Some folks build their sites with light gray on dark gray or the reverse. Cataracts reduce one's ability to decode low contrast; before I had my cataract surgery I could not read sites with gray on gray text, whether light or dark mode.

Nah, that's not React's fault. That's developer's. You can use semantic HTML in react as well.

@dannyman

Oddly I will occasionally switch to dark mode if it’s a rainy day because I get headaches.

Eyes are weird.

Dark mode has been a god send to me. I don’t like white on black - I use dark grey and some very light shade of grey, and on my kobo I use a yellow tint.

I have trouble with brightness in general and wear transitions lenses, or very dark sunglasses when the day is too bright. That may be the reason the light mode bothers me so much.

Some websites are considerate enough to use semantic tags like <article> but this is by no means universal, or even widespread in my experience.

This is more reliable than asking millions of random web sites to somehow understand every nuance of crafting CSS for each audience.

I believe the mainstream operating systems and web browsers already have a variety of accessibility settings, each frustratingly limited in its own way. We all know how to crank the font size up and down!

(Personally, I tend to avoid web sites that DON'T support a dark mode, which I find easier to read, but not to a degree that I need an accommodation. Kagi slow web has a neat switch for rendering random sites in light/dark mode.)

But the browser can only do so much. CSS doesn’t convey the *intent* of elements, only their *appearance*. It’s much worse with React-style pages, in which the CSS *and* html elements have basically zero semantic meaning.

I use Reader mode to get around dark mode, which works sometimes for sites with mostly static blog contents, but a wholesale rewriting of the page style basically requires reading the minds of the developers.

I’m most sensitive to anything that look like bars: repeating strips of high contrast light against dark, like prison cell bars in old cartoons; these patterns cause severe afterimages, often lasting minutes.

My pet theory is that *light areas* in general cause afterimages for me overall. However, in light mode, the entire window is light, so it makes less difference because I basically get a diffuse, white-rectangle afterimage which doesn’t really interfere with details that I’m trying to focus on (it may reduce contrast somewhat in my brain but it’s fine). But in dark mode, the only bright things that cause afterimages are the fine detail (text), so as I move around these afterimages interfere severely against the new details I’m trying to read. A similar thing happens with bars when I’m in light mode.

Fortunately, today's CSS and `light-dark()` make supporting user preferences much easier than before.

However, while WCAG2 and APCA allow us to verify that the contrast is sufficient, what are the recommendations regarding excessive contrast?

IMHO, every modern website should support both modes.

In my case, it's the light mode that my aging eyes can no longer tolerate (too bright: my eyes tire quickly).
And while many rightly criticize dark mode for too much contrast between white text and a black background, for me, it's the lack of contrast that too often prevents me from reading without resorting to manual zoom.