For diffs of previous versions ( 1.34.2,1.34.3,1.34.4,1.34.4,1.35.0,1.35.1,1.35.2,1.36.0,1.36.1,1.36.2 ), you may check out eu4-diffs by maxice8.
Inspired by eu4-diffs, I try to use git diff & diff2html to generate it.
Commands eg:
git diff HEAD^ map/ > 1.diff | diff2html -i file -o stdout -- 1.diff > 1.html