No, that's actually how the website looks. On mouseover, a little line appears on the top of the bar item.

Here's a screenshot without any banner:

I'm closing here since it's working as intended. Feel free to comment if you think I'm wrong.

It seems you're right. Why is that distracting pale blue bar there then? It's just noticeable enough to look wrong.

Why is that distracting pale blue bar there then?

Not a web designer but I think is to mark the element your mouse is hovering. I agree it's a puzzling design choice, usually you do that by underling the words or by shading the whole button area with a different colour. I've never seen it done with a thin coloured line appearing on the top of the button.

EDIT: I'm wrong, the red one is to highlight, the blue one in the screenshot is a different thing.

The issue is that the blue bar is always there (only above "Discover Packages") and looks like an obstructed widget; I can understand the red bar that shows up with hover. Also, not a web designer, but did grow up in a graphic design family. This is very odd design.

EDIT: actually I see it, on the "discover packages" item only. I think it's there to highlight it, and it's by design. Sorry for the confusion, but I think this is working as intended (and it's not changed by the banner, it's always like that).

OK. I think it's bad design and probably should be changed; it's distracting and too subtle to actually draw attention to what it might be trying to draw attention to. This issue is not correct for that though and it seems like there's probably little interest in fixing it. If it will be entertained, I'll file an issue, otherwise I will just try to ignore it or continue to use godoc.org.

@kortschak - feel free to file an issue. We can address this with our UX team for the next round of design changes.

/cc @fflewddur @Joanne881107