The snap includes build artifacts under $SNAP/build that shouldn't be there:
$ ls /snap/libreoffice/current/build/libreoffice-6.0/parts/libreoffice/build/workdir/UnpackedTarball/*/src/.libs/
/snap/libreoffice/current/build/libreoffice-6.0/parts/libreoffice/build/workdir/UnpackedTarball/gpgmepp/src/.libs/:
libgpgme.so.11
/snap/libreoffice/current/build/libreoffice-6.0/parts/libreoffice/build/workdir/UnpackedTarball/libassuan/src/.libs/:
libassuan.so.0
Those shared libs are also found under $SNAP/lib/libreoffice/program/.
The command-*.wrapper scripts add those paths to the LD_LIBRARY_PATH.
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=18.04
DISTRIB_CODENAME=bionic
DISTRIB_DESCRIPTION="Ubuntu Bionic Beaver (development branch)"
DESKTOP_SESSION=ubuntu
GTK_MODULES=gail:atk-bridge
HOME=/home/osomon/snap/libreoffice/56
LANG=fr_FR.UTF-8
LC_MONETARY=fr_FR.UTF-8
LC_NAME=fr_FR.UTF-8
LC_NUMERIC=fr_FR.UTF-8
LC_TIME=fr_FR.UTF-8
LD_LIBRARY_PATH=/var/lib/snapd/lib/gl:/var/lib/snapd/lib/gl32:/var/lib/snapd/void:/snap/libreoffice/56/build/libreoffice-6.0/parts/libreoffice/build/workdir/UnpackedTarball/gpgmepp/src/.libs:/snap/libreoffice/56/build/libreoffice-6.0/parts/libreoffice/build/workdir/UnpackedTarball/libassuan/src/.libs:/snap/libreoffice/56/lib/x86_64-linux-gnu:/snap/libreoffice/56/usr/lib:/snap/libreoffice/56/usr/lib/man-db:/snap/libreoffice/56/usr/lib/x86_64-linux-gnu:/snap/libreoffice/56/usr/lib/x86_64-linux-gnu/mesa:/snap/libreoffice/56/usr/lib/x86_64-linux-gnu/mesa-egl:/snap/libreoffice/56/usr/lib/x86_64-linux-gnu/pulseaudio:/snap/libreoffice/56/usr/lib/x86_64-linux-gnu/mesa-egl:/snap/libreoffice/56/usr/lib/x86_64-linux-gnu/mesa::/snap/libreoffice/56/lib:/snap/libreoffice/56/usr/lib:/snap/libreoffice/56/lib/x86_64-linux-gnu:/snap/libreoffice/56/usr/lib/x86_64-linux-gnu
PATH=/snap/libreoffice/56/usr/sbin:/snap/libreoffice/56/usr/bin:/snap/libreoffice/56/sbin:/snap/libreoffice/56/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games
SNAP=/snap/libreoffice/56
SNAP_ARCH=amd64
SNAP_COMMON=/var/snap/libreoffice/common
SNAP_DATA=/var/snap/libreoffice/56
SNAP_LIBRARY_PATH=/var/lib/snapd/lib/gl:/var/lib/snapd/lib/gl32:/var/lib/snapd/void
SNAP_NAME=libreoffice
SNAP_REEXEC=
SNAP_REVISION=56
SNAP_USER_COMMON=/home/osomon/snap/libreoffice/common
SNAP_USER_DATA=/home/osomon/snap/libreoffice/56
SNAP_VERSION=6.0.2.1
TEMPDIR=/tmp
TMPDIR=/run/user/1000/snap.libreoffice
XDG_CONFIG_DIRS=/etc/xdg/xdg-ubuntu:/etc/xdg/xdg-ubuntu:/etc/xdg
XDG_CURRENT_DESKTOP=ubuntu:GNOME
XDG_DATA_DIRS=/usr/share/ubuntu:/usr/share/ubuntu:/usr/local/share:/usr/share:/var/lib/snapd/desktop:/var/lib/snapd/desktop
XDG_RUNTIME_DIR=/run/user/1000/snap.libreoffice
XDG_SESSION_DESKTOP=ubuntu
XDG_SESSION_TYPE=x11
