Footnote in figure caption crashes PDF render

[fuhrmanator]

Bug description

When using a footnote inside a figure caption, Quarto crashes.

I'm converting a pandoc book to Quarto, and I was previously able to use a footnote inside a caption in Pandoc:

![Here's a caption[^1].](images/example.jpg)

[^1]: Here's a footnote.

But it crashes when I try this in quarto, because (I suspect) the footnote is inside the caption (and maybe something's not being escaped properly?):

Latexmk: If appropriate, the -f option can be used to get latexmk
  to try to force complete processing.
Reverting Windows console CPs to (in,out) = (437,65001)
Error producing PDF.
! Argument of \caption@ydblarg has an extra }.
<inserted text>
                \par
l.794   footnote.}.}

I'm running quarto on Windows 10.

quarto check

[>] Checking Quarto installation......OK
      Version: 0.9.577
      Path: C:\Users\fuhrm\AppData\Local\Programs\Quarto\bin\
      CodePage: unknown

[>] Checking basic markdown render....OK

[>] Checking Python 3 installation....OK
      Version: 3.10.2
      Path: C:/Python310/python.exe
      Jupyter: (None)

      Jupyter is not available in this Python installation.
      Install with py -m pip install jupyter

[>] Checking R installation...........(None)

      Unable to locate an installed version of R.
      Install R from https://cloud.r-project.org/

Checklist

• formatted your issue so it is easier for us to read?
• included a minimal, self-contained, and reproducible example?
• documented the quarto version you're running, by providing the output produced by quarto check in a terminal in your issue?
• documented the RStudio IDE version you're running (if applicable), by providing the value displayed in the "About RStudio" main menu dialog?
• documented which operating system you're running? If on Linux, please provide the specific distribution as well.
• upgraded to the latest version, including your versions of R, the RStudio IDE, and relevant R packages?

[dragonstyle]

Some notes as I looked into this a little:

• Footnotes in captions pose a challenge since the footnote will have a tendency to be relocated with other places that use the caption text (e.g. list of figures).

• Could use \protect potentially though not sure that is actually desirable since it doesn't really address issues like the above

• May need to create a caption minus the footnote for the list of figures and use a minipage to keep the footnote with the float.

• It seems like after this, there is still likely to be issues with duplicate printing for long captions.

• Great faq here: https://texfaq.org/FAQ-ftncapt

[mcanouil]

This seems to be solved.

Input	Output
--- format: pdf --- ![Here's a caption[^1].]({{< placeholder >}}) [^1]: Here's a footnote.