I recently updated my mid-2014 MacBook Pro running High Sierra, which was working perfectly to Mojave. As soon as I did this my screen went pixelated (just like if you added noise on photoshop) and the display started to jump around. I turned it off and back on and it seemed to be fine. Around a week later while running Android Studios, it happened again but much worse. Turned it off again, however, was unable to turn it back on.
The guys at the genius bar informed me that there is an issue with the display and they will need to replace the whole top of the Mac costing around $800 and take 10 working days. They told me that it works while being plugged into an external monitor, which it does but is incredibly slow.
Booting into safe mode doesn't help & running the Apple Hardware Test doesn't report any issues.
How could updating to the latest OS have caused this to have happened or could it just be a coincidence? I haven't tried reformatting it yet but could it help? Anyone else experienced this or something similar?