Prerequisites

To build any LibreOffice AppImage, you need the following software already installed on your machine:

cp: standard POSIX utility to copy files;
dpkg: Considering that we build the AppImage from the Debian packages, we definitely need a way to extract the contents from .deb packages;
find: it is used mostly to interact with files inside the downloads and storage paths;
fuse needs to be installed and the relative kernel module needs to be loaded;
rsync: if the repository is remote, loaih can publish directly the contents using rsync and SSH;
sed: used to manipulate some source files;
tar and gzip: used to extract the archives from LibreOffice official websites.