I dont claim to have any idea what the issue is, but you could try zooming in. Vertical letters might be aligning directly over the green cell in the pixel... ehh, I doubt it. But it would be interesting to see if it grows with the font size.
End of jim_viebke's quote
zooming out one level [alt] +scroll wheel so I'm not sure exactly how much zoom got rid of it completely
there's about three zoom levels in total where it appears I also noticed before that viewing angle seems to play a part of it i have a low chair so I tend to look up at the monitor when standing and looking down at it the green lines turned pink
I just never noticed it on any other forums or anywhere else