I have issues with my Mid 2012 MacBook Pro Retina 15.4" (16GB RAM, i7 2.6Ghz, 500GB Flash Drive, Dual Graphic: Intel + Nvidia GT 650M)
Whenever I open and close any of the application, it still stays on desktop for a few minutes - but with very low opacity (5% maybe - visible on pictures below). Is it some kind of glitch which is solvable or it maybe graphic card or screen is damaged?
I tried another macOS install, tried another Hard Disk, tried SMC Reset, Tried VRAM Reset. This is happening in macOS Sierra and macOS Catalina. After reboot it still stays over there for few minutes. I guess it is a screen/monitor defect?
What may be causing this? Is it possible to resolve it? And if yes, how?