Hi @nickng , first of all, thank you so much for creating and maintaining this tool. In my field (anti-censorship), there is a go-to place for people to track the latest and historical related publications, called censorbib (Github repo). And it relies on your bibtex parser.

This pull request enables the support of accent characters in the bib key:

@inproceedings{Müller2024a,

Without this commit, the accent characters will cause the parse error, e.g.:

Cannot parse valid bibtex file example/biblatex-examples.bib: parse failed at 1676:17: syntax error

One real-world use case is available at: NullHypothesis/censorbib#51.