I was thinking how to handle links where we can't determine a working
replacement. For the Chinese 1.6 release notes I went with adding "XXX
(dead link)" markers to at least point out that these are broken. This
seems to be acceptable to me here, since the page contains a couple of
other "XXX"-style TODO-/note-markers.
I'm open for alternative ideas though (or do we have some defined
style/handling for this I missed?).