Create In Launcher.sh

#!/bin/bash 

# Place in ~/.local/share/nautilus/scripts and an option will be added to the
# Nautilus context menu to add the selected file(s) as favorites in the Gnome
# overlay.

IFS_BAK=$IFS
IFS="
"

APP_FOLDER=~/.local/share/applications

mkdir -p ~/.cache/
APPS=$(dconf read /org/gnome/shell/favorite-apps)
echo "dconf write /org/gnome/shell/favorite-apps \"$APPS\"" > ~/.cache/favs-script.backup

for line in $NAUTILUS_SCRIPT_SELECTED_FILE_PATHS; do    
    fname=$(basename $line)
    if [[ "$line" = "" || "$line" = " " ]]; then
        exit
    else
        dsk="$fname.desktop"
        while [ -f "$APP_FOLDER/$dsk" ]; do
            dsk="$fname.$RANDOM.desktop"
        done
        
        cat >"$APP_FOLDER/$dsk" <<EOL
[Desktop Entry]
Name=${fname}
Exec=xdg-open "${line}"
Type=Application
Terminal=false
EOL
        chmod +x "$APP_FOLDER/$dsk"
        
        new_apps="${APPS::-1}, '$dsk']"
        dconf write /org/gnome/shell/favorite-apps "$new_apps"
    fi
done

IFS=$IFS_BAK