[movedx]

Author: write HTML right Me: this green on black background is terrible to read, I'll use reader mode Chrome: this author did not write their HTML correctly, so there is no reader mode available

How ironic.

[exyi]

Firefox's reader mode works just fine. You need a right browser for the right HTML.

... anyway, it bothers me sometimes that I'm not aware of any spec for "reader mode compatibility", did anyone see anything like that?

[zzo38computer]

I use (a old version of) Firefox and can select "View > Page Style > No Style" to disable CSS, and this works OK for me (it is better than some web pages, where this does not work very good, but this one it works good).

I do not know what criteria are needed for the reader mode in Chrome. (The HTML code looks OK to me?)

[frosted-flakes]

I think Reader mode looks for a <main> section. When it's not present it either guesses or doesn't work at all.