diff -up tex/latex/tabu/tabu.sty.fix-longtable tex/latex/tabu/tabu.sty
--- tex/latex/tabu/tabu.sty.fix-longtable 2023-01-07 22:26:25.122509902 -0500
+++ tex/latex/tabu/tabu.sty 2023-01-07 22:27:36.507051072 -0500
@@ -1356,7 +1356,7 @@
\tabuendlongtrial}\egroup % got \tabu@box
}% \tabu@longtrial
\def\tabuendlongtrial{% no @ allowed for \scantokens
- \LT@echunk \global\setbox\@ne \hbox{\unhbox\@ne}\kern\wd\@ne
+ \LT@echunk \global\setbox\LT@gbox \hbox{\unhbox\LT@gbox}\kern\wd\LT@gbox
\LT@get@widths
}% \tabuendlongtrial
\def\tabu@adl@endtrial{% <arydshln in nested trials - problem for global column counters!>