[LaTeX writer] Footnotes don't work in definition list headers

[Siphalor]

> pandoc --version
pandoc 2.19.1
Compiled with pandoc-types 1.22.2.1, texmath 0.12.5.2, skylighting 0.13,
citeproc 0.8.0.1, ipynb 0.2, hslua 2.2.1
Scripting engine: Lua 5.4

---

First off, this is about an edge case in LaTeX.
I fear that solving this edge case in Pandoc will require some serious work, so I don't expect this to be fixed soon.
This issue is therefor more of a tracking issue, maybe accumulating further workarounds in the future.
In the meantime, it may be appropriate for Pandoc to issue a warning/error message in these cases.

Go to workaround section

---

The LaTeX writer currently inlines all footnotes using \footnote{<footnotetext}.
This doesn't work correctly in \item[<text>] declarations though.
In these cases only, the footnote mark will be rendered, not the footnote itself.

An input Markdown document of

Header[^fn]:
:    Some other text.

[^fn]: A footnote.

produces the following LaTeX:

\begin{description}
\tightlist
\item[Header\footnote{A footnote.}:]
Some other text.
\end{description}

Which produces the following PDF output:

Workarounds/Solutions

A discussion of solutions can be found on StackExchange.
The more complete fixes require additional packages and are really not trivial to solve.

A simple workaround for single footnotes that are only used once (referencing footnotes multiple times isn't supported in Pandoc anyway), is to use \footnotemark{} and \footnotetext{<text>} as in the following example:

Header\footnotemark{}:
:    \footnotetext{A footnote}
    Some other text.

which will render to the following LaTeX:

\begin{description}
\item[Header\footnotemark{}:]
\footnotetext{A footnote}

Some other text.
\end{description}

This obviously won't work for multiple footnotes in the same heading.
If this hacky solution is acceptable, I'd probably be able to create a pull request for this behavior.