Source: feynmf Followup-For: Bug #1029439 Assuming that we want to keep the feynmf sources as-is (I think we do; feynmf.dtx hasn't changed[1] since 1996, a sign of stability), then this bug seems like a regression in another component.
Looking at the build logs for a failure-to-build[2] in this thread and a previous successful build[3], it looks like there's some divergence after this common line of output: Writing index file fmfmanps.idx And, reading a few lines below that in what I'm guessing is a LaTeX call stack (a series of package names, one-per-line), the common element that both call stacks originate from is 'l3backend-dvips.def', part of the latex3[4] codebase. My guess would be that something in latex3 has changed over the course of the past year or two that has introduced this problem as a side-effect. The 'l3backend-dvips.def' file is currently part of the 'texlive-latex-base' Debian package. [1] - https://www.ctan.org/tex-archive/macros/latex/contrib/feynmf [2] - https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1029439#5 [3] - https://buildd.debian.org/status/fetch.php?pkg=feynmf&arch=all&ver=1.08-13&stamp=1636243992&raw=0 [4] - https://github.com/latex3/latex3/
