(Preliminary remark: I'm not entirely sure if this type of question, about hardware damage, is encouraged on this SE site. Apologies if it doesn't belong here.)
The screen of my MBP Retina 13' (early 2015) started showing some odd 'stains' a few days ago, covering about 20% of the screen. Didn't think much about it, until I read about 'Staingate' later (silly name, but oh well).
Here's my problem/question:
I'm not sure if what I have is actually damage to the coating (i.e. 'staingate') or not.
On the one hand, the stains looked similar to those on the pictures people posted.
However, before I read about the possible coating issue, I was able to remove these 'stains' with a soft, clean microfiber and some warm water. It took a while to completely do so, basically, rubbing persistently for a while, but without using force, just light pressure.
I am wondering now if (a) these were just regular (but rather persistent) stains, and I simply cleaned the screen, or (b) if I rubbed off what I thought were stains, but in reality, was some screen coating.
Is there any way I can determine this?
For example, how would I be able to tell if my screen lacks the coating? Can you usually see your own reflection in a coated screen if the screen is turned off? I can do so now, but don't recall if that was always the case.
The machine is still under warranty, and if it is in fact screen damage, I will try to get it covered. But before going to the store, I was hoping I could first determine if it's worth/necessary to go there, hence, this question.