GraphicsMagick / ImageMagick in some distros dropping 'default' support for PDF
According to https://bugzilla.opensuse.org/show_bug.cgi?id=1105592#c25 OpenSuSE GraphicskMagick and ImageMagick packages are dropping support for PDF files 'by default'.
I've experienced this on OpenSuSE Leap 42.3 with GraphicsMagick-1.3.25-105.1 (and newer) - to make it work, I had to:
1. Replace the 'packaged' version of /usr/lib64/GraphicsMagick-1.3.25/config/delegates.mgk with an older version from backups - they removed everything regarding PDF and PostScript, that's using Ghostscript (diff is attached)
2. Create a 'wrapper' script /usr/bin/gm-wrapper to add an environment variable 'MAGICK_CODER_STABILITY=BROKEN' before running the actual GM binary (script is attached)
3. Rename /usr/bin/gm to /usr/bin/gm-bin
4. Symlink /usr/bin/gm -> /usr/bin/gm-wrapper
Note that ImageMagick has different workaround(s).
I'm posting this mainly to help others that may experience this issue, but also as a reminder that Typo3 might need to implement a different PDF to image conversion method.