Multiple footnotes in a row are not rendered correctly

[pamolloy]

Problem

When listing more than one footnote in a row without spaces in between them, mdbook only renders the last footnote and at least as of v0.4.48 generates the following warnings.

so-called advanced persistent threats[^10][^18][^5]. Once an exploit is installed,

2025-05-05 21:16:52 [WARN] (mdbook::utils): footnote `10` in `<unknown>` is defined but not referenced
2025-05-05 21:16:52 [WARN] (mdbook::utils): footnote `18` in `<unknown>` is defined but not referenced
2025-05-05 21:16:52 [WARN] (mdbook::utils): footnote `10` in `u-root.md` is defined but not referenced
2025-05-05 21:16:52 [WARN] (mdbook::utils): footnote `18` in `u-root.md` is defined but not referenced

Steps

No response

Possible Solution(s)

No response

Notes

No response

Version

[ehuss]

Thanks for the report! Looks like this has been fixed in pulldown-cmark, but we are currently stuck on an older version.