On the other hand, I can't think of any advantage myself to having these things be discrete boxes, and I know what a search term and a URL is (as I'm sure most users do, give them some credit here). Corner cases rarely happen and if I think something might look like a url but is a search term, you can prepend the term with whitespace. Ultimately having them not be discrete boxes means I can see more of the url before it folds, which I prefer.