\footnotecommand is a fragile command, so An extra `}'??].
If there is no other command to use in its place, you should
\protect immediately before the
[Footnotes in LaTeX section headings]This, however, is a contrived example, because it isn't a good idea to have a footnote in a section heading, as it will also end up in the table of contents, and possibly in page headings.
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