Georges-Etienne Legendre - SearchWP
is a aid to searching from the Firefox search box - it puts your search words available in the search results. They will be listed on the toolbar so you can click to find each word in the pages. Also you can click a highlight button to get them in colour.
Georges-Etienne Legendre - SearchBox Sync
SearchWP only works if you use the Firefox search box - if you use say Google search direct well install Sync.
I did not want google toolbar as it clutters up the browser with features I find hard to see the point of. I do have Google desktop and use the taskbar search box so Sync is most useful.
Both addons work for other search engines