[tex4ht] Epub index entries with umlauts (and other special characters)

["Jürgen Hubert"]

Thanks for the help with getting a hyperlinked index in epub files! After some further discussions on the TeX Stack Exchange I was able to figure out a solution. The problem was that xindy-lisp.exe cannot cope with Umlauts in file names - you can read the details here, if you are interested:

https://tex.stackexchange.com/questions/451221/getting-xindy-to-run-from-a-directory-with-an-umlaut-in-its-path/451494

However, umlauts continue to bedevil me when making index entries. I have once again generated a sample tex file for showcasing the problem:

https://drive.google.com/open?id=1vrgnFB-UPOgMq0QLw2mWTMk8GZ3LjcWx

When I compile it with pdflatex + MakeIndex in MiKTeX, the index is created properly without any problems:

https://drive.google.com/open?id=1_g9ll3ganZM4DDyD3R1CkahwVYX8gjZz

However, when I try to compile it with the usual command:

tex4ebook -m index -c myconfig.cfg -e mybuild.mk4 Test2.tex

using the same myconfig.cfg and mybuild.mk4 as last time:

https://drive.google.com/open?id=1juflQcym-qvLheMEr26a0CtsbakFNr5K
https://drive.google.com/open?id=1TkxYOozHi_188g7FpwUZ0s_Zxnl-O_fq

the compiling process produces all sorts of error messages apparently centered on the entries with umlauts:

! Missing \endcsname inserted.
<to be read again> 
                   \let 
l.9   \item \idxkeyword{Riesending-Schachth\"ohle}
                                                  , \idxlocator{1}
? 

You can see the logfile here:

https://drive.google.com/open?id=1Q8tKD-yrl1yBV0Zpf0892pacBQGtpLzj

So... what am I still doing wrong?


Best regards,

- Jürgen Hubert