As far as I can tell this seems to be for deleting application data (~/.var/app/*), whereas flatpak uninstall --unused is for uninstalling runtimes that are no longer needed.
Because there are distros, like fedora for one, that have flat packs installable by the likes of discovery on KDE that doesn’t require CLI useage for install or uninstall of flatpacks
For fun, a shell script for the same functionality:
#!/bin/sh
br="$(printf "\n")" # Obtain a line-break
# If RM_CMD is unset, use trash-cli
if [ -z ${RM_CMD+y} ]; then RM_CMD="trash"; fi
# List of apps. The leading br is necessary for later pattern matching
apps="$br$(flatpak list --columns=application)" || exit 1
cd ~/.var/app || exit 1
for app in *; do
case "$apps" in
*"$br$app$br"*) ;; # Matches if $app is in the list (installed)
*)
printf 'Removing app data %s\n' "${app}"
"$RM_CMD" "./${app}"
;;
esac
done
#!/bin/bash
# List contents of ~/.var/app/
files=$(ls -1 ~/.var/app/)
# Loop through each element of the folder
for file in $files; do
# Set the name as a variable
app_name="${file##*/}"
# Check if a flatpak app of that name is installed
if ! flatpak list 2> /dev/null | grep -qw $app_name; then
# Ask the user to delete the folder
read -p "The app $app_name is not installed. Do you want to delete its folder? (y/n): " choice
case "$choice" in
[Yy]* )
# Remove the folder recursively
rm -rf ~/.var/app/$file;;
[Nn]* )
echo "Skipping deletion of $app_name folder.";;
* )
echo "Invalid input. Skipping deletion of $app_name folder.";;
esac
fi
done
echo "All Apps checked."