I found these small vertical cracks in the lug of the headtube. I don't know enough about bikes/frames to know if this is a major issue or not. It doesn't appear that they extend up above into the top of the lug. (What looks like dirt along the top ridge of the lug there is a network of paint cracking that doesn't appear to be an extension of the cracks that run vertically up the serial number)
I can't even quite tell if the vertical cracks are limited to the paint, or if they actually extend into the structure of the lug. Just looking for some opinions, I know it's very hard to give any definitive answers based on two pictures. (1987 Panasonic DX1000 is the bike in question)
Thanks