bug#17966: 24.4.50; Error while saving bookmarks: Unknown button type `help-xref'

[Glenn Morris]

Dani Moncayo wrote:

> emacs -Q
> (set-language-environment 'latin-1)
> (info "(emacs)Regexp Backslash")
> C-u 9 C-n
> C-x r m foo RET
> M-x bookmark-save RET
>
> At that moment, a *Bookmarks* buffers appears and the echo area shows
> the message "Unknown button type `help-xref'".

I can't reproduce this with current trunk on GNU/Linux.
Perhaps it depends on pre-existing contents of the bookmarks file;
mine is empty.