For those not familiar: tabbed browsing (complete with closed page history and undo), whole page zoom, a search engine search bar (and then address bar searching), a download manager, middle click to open in new tab, speed dial/"top sites" for quick navigation in new tabs, and restoring open pages/tabs after the browser has closed or crashed are some of the features "Opera had first."

NetCaptor had tabs before Opera, and that probably wasn't the first browser to have tabs either.