Last Modified: KB » WP Site Search Pro
Can the shortcode be used in a widget?

This is not recommended due to size limitations in most widgetized areas. Instead, we recommend using the built-in Search Widget that comes with WordPress. WP Site Search redirects WordPress searches to the Page configured to show WP Site Search results.

If you configure WP Site Search to handle WordPress searches (enabled by default), then the search box in the default built-in WordPress Search widget will automatically return WP Site Search results for you; i.e., in a stand-alone page so that search results can be navigated properly.

See also: Redirecting WP Searches