Dan Davison writes:
> Bug report
> ==========
> If I have this:
>
> A [[file:zz.org::#mytarget][link]] to a target with a custom ID
>
> and export it to HTML, I get
>
> A <a href="zz.html##mytarget">link</a> to a target with a custom ID
>
> which (in firefox on linux) links to the file but does not jump to the
> target. However, if I change the '##' to '#' then firefox jumps to the
> correct location. Is this an org bug?
>
> Very tentatively proposed patch
> ===============================
> I've investigated a bit (notes below), resulting in this proposed patch:
>
> --8<---------------cut here---------------start------------->8---
> diff --git a/lisp/org-html.el b/lisp/org-html.el
> index aa70408..5ee5b19 100644
> --- a/lisp/org-html.el
> +++ b/lisp/org-html.el
> @@ -1110,7 +1110,7 @@ lang=\"%s\" xml:lang=\"%s\">
> (abs-p (file-name-absolute-p filename))
> thefile file-is-image-p search)
> (save-match-data
> - (if (string-match "::\\(.*\\)" filename)
> + (if (string-match "::#?\\(.*\\)" filename)
> (setq search (match-string 1 filename)
> filename (replace-match "" t nil filename)))
> (setq valid
> --8<---------------cut here---------------end--------------->8---
>
> Doc patch
> =========
> The link above (file:zz.org::#mytarget) was created by C-c l on a
> heading with a CUSTOM_ID property. However, I couldn't see where in the
> manual links of this form are documented. Do we need to add this link
> type to section 4.7 "Search options in file links", e.g.
>
> --8<---------------cut here---------------start------------->8---
> diff --git a/doc/org.texi b/doc/org.texi
> index f49f056..c8cc1a5 100644
> --- a/doc/org.texi
> +++ b/doc/org.texi
> @@ -3116,6 +3116,7 @@ link, together with an explanation:
> [[file:~/code/main.c::255]]
> [[file:~/xx.org::My Target]]
> [[file:~/xx.org::*My Target]]
> +[[file:~/xx.org::#my-custom-id]]
> [[file:~/xx.org::/regexp/]]
> @end example
>
> @@ -3130,6 +3131,8 @@ link will become an HTML reference to the corresponding named anchor in
> the linked file.
> @item *My Target
> In an Org file, restrict search to headlines.
> +@item #my-custom-id
> +Link to a heading with a @code{CUSTOM_ID} property
> @item /regexp/
> Do a regular expression search for @code{regexp}. This uses the Emacs
> command @code{occur} to list all matches in a separate window. If the
> --8<---------------cut here---------------end--------------->8---
>
> Notes
> =====
> At line 1134 of org-html.el there is
>
> (setq thefile (concat thefile "#"
> (org-solidify-link-text
> (org-link-unescape search)))))
>
> during evaluation of which 'search is bound to "#mytarget", which
> suggested that the problem might be in the regexp parsing creating
> 'search.
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