Stefan Kangas <stefan@marxist.se> writes:

>> (It's true that this mostly just applies gnu.org style, but you could
>> always stop doing so.)
>
> But it seems better that the GNU stylesheet is updated, so that this is
> fixed for everyone and not just for Emacs.

Yes.  The problem seems to be here in style.css:

/* For navigation links */
.node a, .header a {display: inline-block;line-height: 2em;}

Having the <a> in the header be inline-block apparently makes
Chrome-based mobile browsers display the links very weirdly.

To test on a Chromium browser, go to this page:

https://www.gnu.org/software/emacs/manual/html_node/emacs/Basic-Minibuffer.html

And then use Developer Tools to switch to mobile view, and you should
see the problems: