I'm not sure, but the phrase "early browser innovations that first saw the light of day over at Opera Software, including tabbed browsing, speed dial, mouse gestures and integrated search" might be a hint. It's hard to imagine now, but Opera had tabs years before any other browser did (maybe even from the start? I started using Opera with version 5 or 6). Opera was also first with those other features, although (iirc) not by as large of a margin as with tabs.