In Launchpad, URL's with quotes (", not %22), such as http://www.google.com/search?q="foo", do not display correctly. They are only highlighted as links up to (but not including) the opening single-quote. This is part of the mechanism whereby Launchpad correctly displays URL's that are themselves contained inside quotes (even if they are at the very end), but it seems that a slight modification to produce a more sophisticated approach to " characters, whereby pairs of "" are treated like pairs of () are currently treated, would produce better results. While URL's containing " characters should ideally have them escaped to yield %22, many web browsers do not do this automatically when copying them to the clipboard from the address bar, and if the URL is part of a listing (for example, copied from a file or a console), then its unescaped " characters may need to be retained for accuracy.
URL's containing " characters are posted on Launchpad from time to time, such as in the first (and currently only) reply in https://answers.launchpad.net/ubuntu/+source/build-essential/+question/153702.
