I first used Opera in December of '96 and it's never tried to be an OS, not once. Mozilla tried it with FirefoxOS based on Gecko and Palm tried it with WebOS, heck even Microsoft tried with Trident somewhat, but no, Opera never tried with the Presto engine or Electra before that. What Opera did was bundle lots of features and offer a nice MDI interface before anyone had the superior tabbed browsing that Mozilla and Firefox popularized.