There is a broken link on the emacs manual introduction page:
https://www.gnu.org/software/emacs/manual/html_node/emacs/Intro.html

The link that's broken is the  'See Preface' link near the end of the last
paragraph.

It is currently linked to this non-existent page:
https://www.gnu.org/software/emacs/manual/html_node/eintr_html/index.html#Top

It most likely was meant to post here without the "_html":
https://www.gnu.org/software/emacs/manual/html_node/eintr/index.html

Or maybe even here if pointing directly to where the preface is referenced
on that page:
https://www.gnu.org/software/emacs/manual/html_node/eintr/index.html#toc-Preface-1

Thanks
Brian Bilgere