I've been a great fan of Opera but this update makes me think about switching to another browser. Two points:
- Instant search accessible from the sidebar was an extremely useful feature. I can't see any reason to give it up.
- Replacing quick access to recently closed/open tabs by search in open tabs only is a mistake. Quick access to recently closed is much more useful than going into history which people usually use to make more detailed and reaching further back searches.
Consider bringing those two features back.