Error message when using footcite from sphinxcontrib-bibtex in a markdown file (but not in rst file)

Describe the bug

Hi there! I want to use the footcite directive of sphinxcontrib-bibtex. However, when I use this directive in a markdown file (ending .md , and as {footcite}) jupyter-book throws an error:

/Users/robert/git/jupyterbookdemo/book/markdown.md:: WARNING: No footnote definitions found for label: 'holdgraf_evidence_2014' [myst.footnote]

When I use the same directive in a RST file (ending .rst, and as :footcite:), no such error occurs.

To Reproduce

I attach a zip file of a minimal example, including a build log in the file build.log:

zippedbook.zip

Expected behavior

no such error message

Environment

• Python Version [e.g. 3.7.1]: 2.7.16
• Package versions or output of jupyter-book --version: 0.10.2
• Operating System: macOS 10.15.7

Additional context

none.

[robertgiessmann]

hi @hildeweerts , our workaround is to filter the build log afterwards… Far from optimal, but here is the code:

https://github.com/FAIRplus/the-fair-cookbook/blob/c3a544400345ff48e301c505ff387fb4171f03ef/scripts/extract-warnings.sh

cat _build/cleaned_build.log | grep "WARNING" | grep -vE "\.md:: WARNING: No footnote definitions found for label: '(.*)' \[myst\.footnote\]" | grep -vE "WARNING: image file not readable: (.*)\.mmd\.png" | grep -v "/content/recipes/help/myst.md:" | grep -v "/content/recipes/help/myst.md.rst:" | grep "WARNING" test $? -eq 1 ## grep gives exit code 1 if no line found (== no errors)

[mmcky]

@AakashGfude I know you’ve recently been looking at footnotes and bibtex citations. When you get a chance could you take a look at this issue?