make teckids2style compatible with scrlttr2 document class

teckids2style.sty

@@ -2,7 +2,7 @@
 %-
 % Copyright © 2013, 2015
 %	Dominik George <dominik.george@teckids.org>
-% Copyright © 2014, 2015, 2017, 2018, 2020
+% Copyright © 2014, 2015, 2017, 2018, 2020, 2024
 %	Thorsten “mirabilos” Glaser <thorsten.glaser@teckids.org>
 % Copyright © 2015, 2016, 2017, 2019
 %	Thorsten Glaser <t.glaser@tarent.de>
@@ -31,7 +31,7 @@
 % • (em dash) → \dash
 
 \NeedsTeXFormat{LaTeX2e}%
-\ProvidesPackage{teckids2style}[2021/11/19 1.18 Teckids TeX/LaTeX style, second epoch]% for Tₑχ/LᴬTᴇΧ
+\ProvidesPackage{teckids2style}[2024/06/11 1.19 Teckids TeX/LaTeX style, second epoch]% for Tₑχ/LᴬTᴇΧ
 
 \RequirePackage{accsupp}%
 \RequirePackage[utf8]{inputenc}%
@@ -61,7 +61,9 @@
 \RequirePackage[encoding,filenameencoding=utf8]{grffile}%
 \RequirePackage{framed}%
 \RequirePackage[export]{adjustbox}%
-\RequirePackage[section]{placeins}%
+\ifcsname RedeclareSectionCommand\endcsname% (nicht in Briefen)
+ \RequirePackage[section]{placeins}%
+\fi%
 \RequirePackage[pdftex,unicode]{hyperref}%
 
 % Debian stretch compatibility glue
@@ -270,7 +272,8 @@
 \newcommand{\angekreuzteskaestchen}{\CheckedBox\hspace{0.1cm}}%
 \newcommand{\ankreuzkaestchen}{\Square\hspace{0.1cm}}%
 
-% Inhaltsverzeichnis
+% Inhaltsverzeichnis (nicht in Briefen)
+\ifcsname RedeclareSectionCommand\endcsname%
 \addtocontents{toc}{\protect\thispagestyle{fancy}}%
 \RedeclareSectionCommand[tocbeforeskip=10pt plus 4pt minus 2pt]{section}
 \RedeclareSectionCommand[tocnumwidth=2.8em]{subsection}
@@ -284,6 +287,7 @@
  % deliberately no % at end of line!
  \newpage
 }%
+\fi%
 
 % Listings