Documentation builds have been failing with this error:
$ make html
Running Sphinx v3.4.3
loading pickled environment... failed
failed: No module named 'sphinxcontrib.bibtex.cache'
Extension error:
You must configure the bibtex_bibfiles setting
make: *** [html] Error 2
Documentation builds have been failing with this error:
A quick fix is to set the
sphinxcontrib-bibtex
version to<2.0.0
(as per this issue: https://github.com/executablebooks/jupyter-book/issues/1137)