firefox-23.0-1.fc19.x86_64 keyword.URL setting in about:config is not respected. If keyword.enable is true searches get directed to the search provider as assigned in the search bar instead of using the string in keyword.URL. To reproduce: 1. In about:config set keyword.URL to "https://duckduckgo.com/html?q=". 2. Ensure your searh provider is set to something that is not DDG (e.g. Google) in the search bar. 3. In another tab type at least two words into the address bar and hit enter. 4. Observe the search query being sent to the provider set in the search bar instead of DDG.
The feature was removed in version 23. Further discussion at https://bugzilla.mozilla.org/show_bug.cgi?id=873734 .