In the guacamole-manual Makefile, files are found using
find -path "./src/*" ...
The "-path" part is not in POSIX. It fails on Mac OSX 10.15:
> find -path "./src/" -name ".md"
find: illegal option – p
usage: find [-H | -L | -P] [-EXdsx] [-f path] path ... [expression]
find [-H | -L | -P] [-EXdsx] -f path [path ...] [expression]
I have a fix for this, just need an issue number for the PR