For the ones in a hurry: YES, this worked for me, the stains on my MacBook Pro (Late 2013) display are gone completely. NO, you will not be bamboozled, fools day was two days ago. YES, do try this at home. NO, you will only need the blue liquid, although the yellow one is highly recommended.
After splurging almost two months salary on my first MacBook Pro almost 10 years ago I surely was a member of the SIG “I can’t stand any stain on my display”. Although lately this was worsened by having to wear glasses which made me wonder which surface was the culprit I really got annoyed by the stains on my display: irregularly distributed, a group of them just in the center, visible any time especially when writing.
When I stumbled upon a YouTube video claiming “Listerine did it” I just could not believe this, it was two days ago. Searching the web for this I found many, many reports about being able to remove the stains, which are in fact some sort of anti-glare coating, I learned. Or the remaining parts of it. The last time Apple built non-glare displays was 2011 I think (I own one on my backup MacBook — perfect, but history). And out of numerous sayings “This … worked for me”, “This … did not”, “took only 5 Minutes”, “took 30 minutes” I distilled the main fact: you need alcohol.
You need something containing alcohol as this is able to remove the coating, listerine (“cool mint”, don’t think this matters) does this as do many other fluids. So perhaps even whisky would work but you will need it mainly for you until you really know that it is working and you are not bricking your beloved device — there are warning voices too on the web NOT to try this.
So just pour some listerine into a cup, take a (microfibre) cloth and begin to rub the stains gently: you will not see instant success but rather a continuous shrinking of the coating, so be patient. It took me about 30 minutes to work every area of the screen, now it is black and shining but very very clean. Recommended!
Time to celebrate. Use the green bottle for this.