It would appear that the junction of the lug and top tube rigth above the serial number was not brazed, paint is partially hiding this. The fact that the crack goes right through the serial number stamping "1" makes one think that this was a stress riser, and a thinning of the material right near the end of the non-existant braze. I'm wondering, however, how structural this is. It's odd since Panasonic was considered a fairly high quality frame shop, if indeed it were built there.
Removal of paint in the area is the only way to see if indeed it is cracked.
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If someone tells you that you have enough bicycles and you don't need any more, stop talking to them. You don't need that kind of negativity in your life.