A: Some browsers (most browsers?) interpret a carriage return between images as a space. A few browsers don't. It's that simple. The little blue dash is simply the link underlining an empty space. The cure is to eliminate carriage returns right before or right after the image.
This is the markup for the above images:
If we were to change it to this we would eliminate the little blue dashes:
Another adjustment and the spaces disappear too:
Is this a pain in the butt? Only if you don't understand what's happening and how to fix it. Is Browser A a crappy browser? Not necessarily, it's just different than Browser B. Browsers sometimes do different things with the same markup.
