has a very long string in it's <code>

No, the problem was that it was not in <code> tags. And your long line isn't either, despite you having put a </code> on the end of it, else it wouldn't cause a width problem for people who have their settings set up correctly for their browsing environment. Note that a long string of non-whitespace characters doesn't get wrapped if there are no newlines inside of the <code> tags with it.