[tex4ht] indexing4ht and accented characters

[Michal Hoftich]

Hello LianTze,

> (Note that if \index{láboris} is changed to \index{laboris} then this can be compiled with tex4book + xindy perfectly.)
>

indexing system provided by indexing4ht is a bit fragile. It is better
to use the native indexing support provided by TeX4ht. You don't need
to load indexing4ht at all, you just need to use one of supported
indexing commands (makeindex, xindy, xindex) in the .mk4 file. See
https://www.kodymirus.cz/make4ht/make4ht-doc.html#x1-300007.1 for the
available options.

It is unfortunately  not possible to use them from Latexmk, because
these commands need to preprocess the .idx and .ind files.

I can compile your file correctly using the following build file:

Make:latexmk {}
Make:xindex {}
Make:htlatex {}

Best regards,
Michal