I don't understand why this bug is still open.I know that some libraries like curl and openssl were not thread-safe, which could have explained it.
The argument used in the post is that fitz is not mature. That was in 2013.There are some patches to solve this problem : www.linuxfromscratch.org/patches/blfs/svn/mupdf-1.16.1-shared_libs-1.patch
