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ID 169🔗 Nicola Talbot 🦜 2020-10-20 13:23:40 Closed (Can Not Implement) jmlrbook 1.28 Fails with new kernel (extra \endgroup)

## Description

The jmlrbook class doesn’t work with the new LaTeX kernel 2020-10-09. The provided MWE fails with the error
! Extra \endgroup


## MWE

\documentclass{jmlrbook}

\title{A Sample Book}

\author[Anne Editor et al.]{Anne Editor and Anne Other Editor}

\begin{document}
\maketitle
\end{document}


## Evaluation

This is a known issue. Unfortunately the incompatibilities with jmlrbook.cls and the new kernel can't be fixed until the dependent combine.cls is updated to work with this kernel.

This means that jmlrbook is now obsolete. Production editors need to set the first page number for each article using \firstpageno{N} and create the proceedings bib file according to the PMLR specifications. If you need to combine all articles into a book, consider using the pdfpages package.

This issue does not affect jmlr.cls which is used by article authors.

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