Find outdated .desktop files

find_outdated_desktop_files.sh

#!/bin/bash -

grep -a -r -P -o '(?:(?<=Exec=)([^"]\S+)|(?<=Exec=")(\S+)(?="))' \
    -- /{usr,home/*/.local}/share/applications | sort -u | \
    while read m; do
        desktop_file="${m%:*}"
        exec_name="${m##*:}"
        
        if ! command -v "$exec_name" 2>&1 >/dev/null; then
            echo "$desktop_file|$exec_name"
        fi
    done