It may be that the default beamer template now includes a package that already loads geometry.
See https://tex.stackexchange.com/questions/266995/latex-error-option-clash-for-package-geometry If so, you should be able to work around this by doing this instead: header-includes: - '\geometry{margin=1in}' Benoît <bdej...@gmail.com> writes: > Package: pandoc > Version: 2.2-1 > Severity: normal > > Dear Maintainer, > > Rendering into beamer no longer works (was ok this since 1.7): > > > --- > author: Benoît > institution: ABC > title: ABC D > date: 2018 > theme: Hannover > toc: true > papersize: a4 > geometry: margin=1.5cm > pagenumbering: true > --- > > > # Hello > Hello > > > > $ pandoc --slide-level 2 -t beamer a.md -o a.pdf > Error producing PDF. > ! LaTeX Error: Option clash for package geometry. > > See the LaTeX manual or LaTeX Companion for explanation. > Type H <return> for immediate help. > ... > > l.44 \newif > > > -- System Information: > Debian Release: buster/sid > APT prefers unstable-debug > APT policy: (500, 'unstable-debug'), (500, 'unstable'), (1, > 'experimental-debug'), (1, 'experimental') > Architecture: amd64 (x86_64) > Foreign Architectures: i386 > > Kernel: Linux 4.15.0-1-amd64 (SMP w/2 CPU cores) > Locale: LANG=fr_FR.UTF-8, LC_CTYPE=fr_FR.UTF-8 (charmap=UTF-8), > LANGUAGE=fr_FR.UTF-8 (charmap=UTF-8) > Shell: /bin/sh linked to /bin/bash > Init: systemd (via /run/systemd/system) > LSM: AppArmor: enabled > > Versions of packages pandoc depends on: > ii libc6 2.27-3 > ii libffi6 3.2.1-8 > ii libgmp10 2:6.1.2+dfsg-3 > ii liblua5.1-0 5.1.5-8.1+b2 > ii libpcre3 2:8.39-9 > ii libyaml-0-2 0.1.7-2 > ii pandoc-data 2.2-1 > ii zlib1g 1:1.2.11.dfsg-1 > > pandoc recommends no packages. > > Versions of packages pandoc suggests: > pn context <none> > pn ghc <none> > ii groff 1.22.3-10 > ii librsvg2-bin 2.40.20-2 > ii nodejs 8.9.3~dfsg-12 > pn pandoc-citeproc <none> > ii perl 5.26.2-2 > pn php <none> > ii python 2.7.15~rc1-1 > ii r-base-core 3.4.4-1 > ii ruby 1:2.5.1 > ii texlive-latex-extra 2018.20180416-1 > ii texlive-latex-recommended 2018.20180416-1 > pn texlive-luatex <none> > pn texlive-xetex <none> > ii wkhtmltopdf 0.12.4-1 > > -- debconf-show failed
