error: pathspec 'mupdf/thirdparty/jpeg' did not match any file(s) known to git

libres-MacBook:src-readonly libre$ git clone https://github.com/Legimet/nPDF.git
Cloning into 'nPDF'...
remote: Enumerating objects: 4256, done.
remote: Total 4256 (delta 0), reused 0 (delta 0), pack-reused 4256
Receiving objects: 100% (4256/4256), 42.24 MiB | 689.00 KiB/s, done.
Resolving deltas: 100% (2451/2451), done.
libres-MacBook:src-readonly libre$ cd nPDF/
libres-MacBook:nPDF libre$ git submodule init
Submodule 'thirdparty/curl' (git://git.ghostscript.com/thirdparty-curl.git) registered for path 'mupdf/thirdparty/curl'
Submodule 'thirdparty/freeglut' (git://git.ghostscript.com/thirdparty-freeglut.git) registered for path 'mupdf/thirdparty/freeglut'
Submodule 'thirdparty/freetype' (git://git.ghostscript.com/thirdparty-freetype2.git) registered for path 'mupdf/thirdparty/freetype'
Submodule 'thirdparty/harfbuzz' (https://github.com/Legimet/thirdparty-harfbuzz.git) registered for path 'mupdf/thirdparty/harfbuzz'
Submodule 'thirdparty/jbig2dec' (git://git.ghostscript.com/jbig2dec.git) registered for path 'mupdf/thirdparty/jbig2dec'
Submodule 'thirdparty/lcms2' (git://git.ghostscript.com/thirdparty-lcms2.git) registered for path 'mupdf/thirdparty/lcms2'
Submodule 'thirdparty/jpeg' (git://git.ghostscript.com/thirdparty-libjpeg.git) registered for path 'mupdf/thirdparty/libjpeg'
Submodule 'thirdparty/mujs' (git://git.ghostscript.com/mujs.git) registered for path 'mupdf/thirdparty/mujs'
Submodule 'thirdparty/openjpeg' (git://git.ghostscript.com/thirdparty-openjpeg.git) registered for path 'mupdf/thirdparty/openjpeg'
Submodule 'thirdparty/zlib' (git://git.ghostscript.com/thirdparty-zlib.git) registered for path 'mupdf/thirdparty/zlib'
libres-MacBook:nPDF libre$ git submodule update mupdf/thirdparty/jbig2dec mupdf/thirdparty/jpeg mupdf/thirdparty/openjpeg
error: pathspec 'mupdf/thirdparty/jpeg' did not match any file(s) known to git

hey man, just saw this now, just replace it with "mupdf/thirdparty/libjpeg", hope this helps