Lol, this was fun. A comment that kept resuscitating after I deleted it. The image at https://drive.google.com/open?id=1nCmYIuS_QLEKbdBU6h2K6UNO3Lu-Bhlf shows the sequence of steps I took. I finally killed it dead as described.
Thanks. This has been filed and the screenshots will hopefully help us to eradicate this once and for all.
Cool, let me know if I can provide any other info.