I am seeing this weird line vertically across the screen of my MBP 13" (early 2015) laptop. The machine had been shipped with OS Yosemite and I have about 4 months ago upgraded it to OS Sierra. I haven't installed any new software recently. This happens often when I quickly switch between tabs while browsing the internet. It stays for less than a second and then goes away. When I switch between once tab at a time I don't see the line (See attached screenshot). I am not sure what this is, but I do know it wasn't there barely a week (or even less) ago. Is this normal for older laptops? Does it have something to do with the logic board or display? And how worried should I be about this? My MBP has given me 3.5 years of service and I am out of extended warranty now. Thanks!