Firstaid index

[FrankMittelbach]

Internal housekeeping

Status of pull request

• Ready to merge

Checklist of required changes before merge will be approved

• Test file(s) added
• Version and date string updated in changed source files
• [n/a] Relevant \changes entries in source included
• Relevant changes.txt updated
• [n/a] Rollback provided (if necessary)?
• [n/a] ltnewsX.tex (and/or latexchanges.tex) updated

first aid for index package to work with 2025/06 release (might be updated by then but ...

[u-fischer]

This doesn't reimplement the code from index that allows to use \index commands with optional argument in sectioning commands:

\documentclass{book}
\usepackage{index}
\makeindex
\pagestyle{headings}
\begin{document}
\showoutput
\tableofcontents
\chapter{\index[default]{blub} abc}
\section{\index[default]{bla} abc}
x \newpage x \newpage x \newpage
\end{document}

gives faulty headers (with this firstaid code):

[FrankMittelbach]

This doesn't reimplement the code from index that allows to use \index commands with optional argument in sectioning commands:

yes, but that doesn't have to go into the firstaid, it should really go into core LaTeX (just didn't got around doing that yet), but it needs to come as well, but I thought of doing this as a separate pr because I hope that this first aid can go out soon again).