Brief outline of the bug
As longtable does not modify the \if@nobreak flag, the spacing after it and before next section title varies according to whether some contents before it provoked or not \@nobreakfalse.
Minimal example showing the bug
\RequirePackage{latexbug}
\documentclass{article}
\usepackage{longtable}
\def\TESTTABLE{%
\begin{longtable}[c]{|l|l|l|}
\caption{Long table before header\strut}
\endfirsthead
\endhead
\endfoot
\endlastfoot
a
&
b
&
c
\\
\hline
1
&
2
&
3
\\
\hline
\end{longtable}
}
\def\SOMERULE{\smash{\rule{2pt}{40pt}}}
\begin{document}
\section{FOO1}
\TESTTABLE
\section{FOO2 is closer to \SOMERULE longtable than FOO3 will be}
AAA
\TESTTABLE
\section{FOO3 more distant \SOMERULE from long table than FOO2}
AAA
\end{document}Log file (required) and possibly PDF file
buglongtable.log
buglongtable.pdf
Brief outline of the bug
As
longtabledoes not modify the\if@nobreakflag, the spacing after it and before next section title varies according to whether some contents before it provoked or not\@nobreakfalse.Minimal example showing the bug
Log file (required) and possibly PDF file
buglongtable.log
buglongtable.pdf