'Thank you for prompt delivery'
'Thank you so much! The picture were exactly as promised and provided a little extra love to our loved one. Thank you for the great work!'
'The flowers came on time and they were beautiful,made my sister very happy and this all that matter!?? will use again! Thanks'
You won't be able to dismiss this by usual means (escape or click button), but you can close it programatically based on user choices or actions.