Respuesta a "Rubbish (insect) under glass iMac 27" 5k late 2015"I have the same exact problem . . it looks like a tiny ant that appears on my 5k Retine 27” screen. Tried tapping, vacuuming, etc without any success. I’ve been told that the monitor and the protective monitor cover are “fused” together making the cleaning or repair a major endeavor. Was also told by a local Mac service tech that it’s impossible for a tiny ant to get in their. Obviously, it IS possible and I have this proof, unfortunately. So far, no real help. Inclined to live with it for fear of the “side effects” which might result from a major repair.