Apple: Retina Macbook Air suffers from the staingate problem
Once, Apple's Macbook Pro notebooks were offered with two different screen-type options: Customers could buy their Macbook Pro laptops either with a glossy, glass-covered screen or a matte screen without the glass-cover. With the arrival of the Retina Macbook Pro in 2013, this choice was no longer offered, as now there was only a single screen option that was glossy. This screen is also glass-covered. To compromise between the matte and glossy screen types, Apple introduced a anti-reflection screen foliage. While the screens were definitely not matte, this feature greatly reduced the reflections. The problem: The screen film turned out to be not very durable. Screens with it sometimes developed stains – a phenomenon so widespread that it even got its own name: Staingate.
The Macbook Air never offered the choice between matte or glossy. All of the Macbook Air screens were glossy. Importantly however, it never featured glass-covered screens; at least until 2018. Two years ago, Apple finally revealed the big update of the Macbook Air, this time with a glass-covered Retina screen. This screen was outfitted with an anti-reflection film as well
A design decision that seems to have backfired, as Apple has confirmed now that "staingate" affects the Apple Macbook Air 2018 as well. "Macrumors" has obtained an internal memo for Apple Service providers about the staingate which now mentions the Macbook Air for the first time. Before, only the discontinued 12 inch Macbook and various Macbook Pro models were officially confirmed to be affected.
If you have a Macbook Air that exhibits the problem, you should contact Apple support, as Apple as a repair program for this problem. With Apple mentioning the Macbook Air 2018 in an official document as an affected machine, there is a good chance that it will be covered.