Hi:
Snap system is a Sandbox way to install now programs in many
GNU / Linux distributions. It was develop by Canonical (Ubuntu) and put
able for all the distributios want to use. It try to solve the problems
of securities because as I understand the software installed by this
way can't access nothing than the place where it is installed. Another
benefits, it is easier to the own or develops of the programs to
prepare software to offer updates to the users (less complicated). It
benefits both sides.
In this links you can find the repositorie of software prepare with
Snap:
https://snapcraft.io/store
and here:
https://snapcraft.io/libreoffice
you can find LibreOffice as snap installation.
Flatpak is other way that born, as I know, as the same time of Snap and
has similar features, but to know what are all the difference between
them, is necessary to googleing because I don't know all of them
although I red a year ago, more less, an articule in the web about this
topic.
If you have problems with the Flatpak installation in GNU / Linux Mint,
why not probe with the Snap option ?
I hope this help,
Jorge Rodríguez