Incompatibility with KOMA-Script classes

[chsk-uk]

The latest release (2.12, CTAN: 2019-09-10), possibly the previous release (2.10, CTAN: 2019-07-17), cannot be loaded at all when using KOMA-Script's ,,scrartcl`` class (and, presumably, other KOMA-Script classs). Here is an MWE:

\documentclass{scrartcl}
\usepackage{titlesec}
\begin{document}
\section{Title}
\end{document}

Compiling this with XeLaTeX (see below for details) yields:

This is XeTeX, Version 3.14159265-2.6-0.999991 (MiKTeX 2.9.7200 64-bit) (preloaded format=xelatex 2019.2.26)  8 OCT 2019 13:04
entering extended mode
**./texstudio_TzzZrd.tex
(texstudio_TzzZrd.tex
LaTeX2e <2018-12-01>
("C:\Program Files\MiKTeX 2.9\tex/latex/koma-script\scrartcl.cls"
Document Class: scrartcl 2019/02/01 v3.26b KOMA-Script document class (article)

[...]

Class scrartcl Warning: Usage of package `titlesec' together
(scrartcl)              with a KOMA-Script class is not recommended.
(scrartcl)              I'd suggest to use the package only
(scrartcl)              if you really need it, because it breaks several
(scrartcl)              KOMA-Script features, i.e., option `headings' and
(scrartcl)              the extended optional argument of the section
(scrartcl)              commands.
(scrartcl)              Nevertheless, using requested
(scrartcl)              package `titlesec' on input line 3.

[...]

Class scrartcl Info: Deactivating the `titlesec' workaround,
(scrartcl)           because package is newer than expected on input line 3.

[...]

! Missing number, treated as zero.
<to be read again> 
                   }
l.4 ^^I\section{Title}
                      
A number should have been here; I inserted `0'.
(If you can't figure out why I needed to see a number,
look up `weird error' in the index to The TeXbook.)

! Illegal unit of measure (pt inserted).
<to be read again> 
                   }
l.4 ^^I\section{Title}
                  
Dimensions can be in units of em, ex, in, pt, pc,
cm, mm, dd, cc, bp, or sp; but yours is a new one!
I'll assume that you meant to say pt, for printer's points.
To recover gracefully from this error, it's best to
delete the erroneous units; e.g., type `2' to delete
two letters. (See Chapter 27 of The TeXbook.)

[...]

I understand that mixing KOMA-Script and titlesec is generally advised against. Nevertheless this used to work.

If I understand the messages correctly, the problem may in fact lie with KOMA-Script; according to komascript.de (in German) the problem is known to the KOMA-Script author, but will not be fixed on KOMA-Script's side. So it would be nice if titlesec could be changed to better accomodate KOMA-Script.

Thanks!

[jbezos]

I'm sorry to say that I don't have time to make titlesec to work with the KOMA classes. And even if I modify titlesec, there is no guarantee that it will work with future versions of KOMA, which are not under my control. See also:

https://tex.stackexchange.com/questions/500970/titlesec-s-update-2-10-2-%e2%86%92-2-11-caused-subparagraphs-not-working-in-scrbookclas?noredirect=1#comment1265340_500970

[chsk-uk]

Understandable. Thank you anyway!