The quick fix when building the image (Dockerfile)
RUN DEBIAN_FRONTEND="noninteractive" apt-get install -y fonts-noto libdbus-glib-1-2 libsm6 libfreetype6 libfontconfig libx11-6 libcairo2 libcups2 libx11-xcb1
PDF to PDF conversion should work fine after this change.
Fixed image can be retrieved from:
docker pull docker.edge.languageweaver.com/mtedge/sdl-mtedge:8.5.8-1