##  app-conf/apt/nosnap.pref
    # To prevent repository packages from triggering the installation of snap,
    # this file forbids snapd from being installed by APT.

    Package: snapd
    Pin: release a=*
    Pin-Priority: -10

    ### Remove snapd applications and service
    snap remove --purge firefox
    snap remove --purge gnome-3-38-2004
    snap remove --purge gtk-common-themes
    snap remove --purge bare
    snap remove --purge core20
    snap remove --purge snapd
    apt-get remove --yes snapd

    # This will prevent snapd from any repository

tested on Ubuntu jammy