remove-snap.sh

#!/usr/bin/env bash
#
# remove-snap.sh
#
# This script:
#   1. Removes all Snap packages and snapd
#   2. Disables and purges snapd
#   3. Blocks snapd from being reinstalled via APT pinning
#   4. Installs GNOME Software (no Snap) + Flatpak plugin
#   5. Installs Flatpak and enables Flathub
#   6. Optionally installs Firefox, Brave, and GNOME Extensions Manager
#
# Tested on Ubuntu 22.04/24.04 style systems.
#
# READ BEFORE RUNNING:
#   - This will run 'rm -rf' on Snap directories (/snap, /var/snap, etc.).
#   - This will modify /etc/apt and add pinning and repos.
#   - Only run if you're sure you don't want Snap at all.

set -euo pipefail

echo "[1/6] Removing installed Snap packages (if present)..."
SNAPS=(
  firefox
  gtk-common-themes
  gnome-42-2204
  snapd-desktop-integration
  snap-store
  firmware-updater
  bare
  core22
  snapd
)

for pkg in "${SNAPS[@]}"; do
  if snap list | awk '{print $1}' | grep -Fxq "$pkg" 2>/dev/null; then
    echo " - Removing snap: $pkg"
    sudo snap remove "$pkg" || true
  else
    echo " - Snap $pkg not installed, skipping"
  fi
done

echo
echo "[2/6] Stopping and disabling snapd service..."
sudo systemctl stop snapd.service snapd.socket snapd.seeded.service 2>/dev/null || true
sudo systemctl disable snapd.service snapd.socket snapd.seeded.service 2>/dev/null || true
sudo systemctl mask snapd.service snapd.socket snapd.seeded.service 2>/dev/null || true

echo
echo "[3/6] Purging snapd package and marking it on hold..."
if dpkg -l | awk '{print $2}' | grep -Fxq "snapd"; then
  sudo apt purge -y snapd
else
  echo " - snapd package already absent"
fi
sudo apt-mark hold snapd || true

echo
echo "[4/6] Removing leftover Snap directories..."
sudo rm -rf /snap /var/snap /var/lib/snapd /var/cache/snapd 2>/dev/null || true
sudo rm -rf "$HOME/snap" 2>/dev/null || true

echo
echo "[5/6] Preventing snapd from ever reinstalling (APT pinning)..."
sudo tee /etc/apt/preferences.d/nosnap.pref > /dev/null <<'EOF'
Package: snapd
Pin: release a=*
Pin-Priority: -10
EOF

echo " - Updating APT after nosnap.pref..."
sudo apt update

echo
echo "[6/6] Installing GNOME Software and Flatpak support..."
sudo apt install -y --install-suggests gnome-software gnome-software-plugin-flatpak

if ! command -v flatpak >/dev/null 2>&1; then
  sudo apt install -y flatpak
else
  echo " - flatpak already installed"
fi

if flatpak remote-list | awk '{print $1}' | grep -Fxq "flathub"; then
  echo " - flathub remote already exists"
else
  sudo flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo
fi

# -------------------------------
# Optional Software Installations
# -------------------------------
echo
read -rp "Do you want to install Firefox (no-Snap .deb from Mozilla)? [y/N] " install_firefox
if [[ "${install_firefox,,}" == "y" || "${install_firefox,,}" == "yes" ]]; then
  echo
  echo "[Optional] Installing Firefox from Mozilla APT repo (no Snap)..."

  sudo install -d -m 0755 /etc/apt/keyrings

  wget -q https://packages.mozilla.org/apt/repo-signing-key.gpg -O- \
    | sudo tee /etc/apt/keyrings/packages.mozilla.org.asc > /dev/null

  echo "deb [signed-by=/etc/apt/keyrings/packages.mozilla.org.asc] https://packages.mozilla.org/apt mozilla main" \
    | sudo tee /etc/apt/sources.list.d/mozilla.list > /dev/null

  sudo tee /etc/apt/preferences.d/mozilla > /dev/null <<'EOF'
Package: *
Pin: origin packages.mozilla.org
Pin-Priority: 1000
EOF

  sudo apt update
  sudo apt install -y firefox
else
  echo " - Skipping Firefox installation"
fi

echo
read -rp "Do you want to install Brave Browser? [y/N] " install_brave
if [[ "${install_brave,,}" == "y" || "${install_brave,,}" == "yes" ]]; then
  echo
  echo "[Optional] Installing Brave Browser from official APT repo..."

  if ! command -v curl >/dev/null 2>&1; then
    echo " - curl not found, installing curl..."
    sudo apt update
    sudo apt install -y curl
  fi

  sudo install -d -m 0755 /etc/apt/keyrings

  curl -fsSL https://brave-browser-apt-release.s3.brave.com/brave-browser-archive-keyring.gpg \
    | sudo tee /etc/apt/keyrings/brave-browser-archive-keyring.gpg > /dev/null

  echo "deb [signed-by=/etc/apt/keyrings/brave-browser-archive-keyring.gpg arch=amd64] https://brave-browser-apt-release.s3.brave.com/ stable main" \
    | sudo tee /etc/apt/sources.list.d/brave-browser-release.list > /dev/null

  sudo apt update
  sudo apt install -y brave-browser
else
  echo " - Skipping Brave installation"
fi

echo
read -rp "Do you want to install GNOME Extensions Manager (Flatpak)? [y/N] " install_extensions_manager
if [[ "${install_extensions_manager,,}" == "y" || "${install_extensions_manager,,}" == "yes" ]]; then
  echo
  echo "[Optional] Installing GNOME Extensions Manager from Flathub..."
  flatpak install -y flathub com.mattjakeman.ExtensionManager
else
  echo " - Skipping GNOME Extensions Manager installation"
fi

echo
echo "All done!"
echo "You are now Snap-free. GNOME Software and Flatpak/Flathub are configured."
echo "If selected, Firefox, Brave, and/or GNOME Extensions Manager have been installed."