FireFox comes with some built-in smart keywords:
- google -> http://www.google.com/search?q=%s
- dict -> http://dictionary.reference.com/search?q=%s
- stock -> http://www.google.com/search?q=stocks:%s
- wp -> http://en.wikipedia.org/wiki/Special:Search?search=%s
The easiest way to add a smart keyword is to right-click in a search field on a web page and choose “Add a Keyword for this Search.”
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Now I can search for a word in the Dutch version of Wikipedia by typing "wpn" and the search term(s) in the address bar (pressing CTRL+L will move the cursor to the address bar). For example:
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Looking at the bookmark Properties, the location that is used is http://nl.wikipedia.org/wiki/Speciaal:Zoeken?search=%s