Find All is compatible with Firefox 24. For Firefox 25+, try FindBar Tweak instead.
This add-on replaces the find bar's Highlight All button with a powerful Find All button, which highlights all search terms found and displays them in an easy to view list. The list displays a few words before and after the search term so you can quickly see the context of each match. It also shows a total of how many times the search term was found on the page.How to use Find All
Once it is installed, start Firefox and click on Firefox menu > Find...
By default, the Find All button replaces the Highlight All button on the Find bar. If you would like to have the Highlight All button back on the Find bar, you may set this preference in the Find All add-on options dialog (Firefox menu > Add-ons, click Options button on Find All). You may also set a preference to not show the list of found results when the Find All button is clicked (only the total number of matches will show in the Find bar status area).
Find All also works in the browser's View Source window.
Note: Find All may not be compatible with other extensions/themes that modify the find bar or the add-on bar. Also, Find All may not work well on web pages that contain lots of dynamic (i.e., frequently updated in real time) content.Screenshots
Screenshot 1: Firefox window showing the results list after having clicked the Find All button