After using my HP Pro Slate 12 Tablet for about 3 years (but very seldom) it started getting big air bubbles underneath the glass and showing heavy backlight bleeding (see images attached). I always kept it in a case and rarely transported it. I wonder if someone experienced the same or has a clue what might cause this issue. It was not a cheap machine and it's sad to see HP building stuff that behaves like this. I never saw anything similar on tablets from other manufacturers.