Optimizations
# MacOS
preview > export -> reduce size
# Imagick
magick -compress Zip -density 20x20 input.pdf output.pdf
# Ghostscript
gs -sDEVICE=pdfwrite -dNOPAUSE -dQUIET -dBATCH -dPDFSETTINGS=/screen -dCompatibilityLevel=1.4 -sOutputFile=output.pdf input.pdf