You may have read by now that the first public alpha of Kestrel is planned for next Tuesday, September 4th. Since there's still a couple days before then, we wanted to tell you a bit more about what to expect from Kestrel. Kestrel is the product of over a year of development, which began in our code repository on June 20, 2006. Since then, we've developed several major new features, fixed thousands of bugs, and made Opera the best it's ever been.

We've been dropping bits of information about Kestrel for several months now and it's time to reveal some more about this release. Users have suggested many new features and we're happy to be able to deliver some of them this time around. In Kestrel, we focused on five things: performance, site compatibility, accessibility, OS integration, and Opera Mail.

Performance

Opera's already fast, but we're not satisfied with fast. We want to do even better, which is why we've been focusing on a lot of performance problems over the past year. Two of the outcomes of this focus are our new ECMAscript engine and the new indexing and storage back-ends for Opera Mail. The new ECMAscript engine has been a pet project of our lead ECMAscript developer for several years and he's recently passed on his pride and joy to two other programming language junkies. The new ECMAscript engine uses fewer resources than anything we've done previously. Many parts are faster than the previous ECMAscript engine, but we still are working on further boosting the speed of the engine.

Opera Mail has seen similar improvements. The new indexing and storage back-ends use less memory, access the hard drive less often, and perform normal functions faster. Many users have complained about freezes when Opera Mail is checking for new mail or newsfeeds. These problems are largely gone. Mail checking and processing is faster and indexing and searching are more reliable.

Many other parts of Opera have seen speed boosts as well. The end result is faster, smoother surfing. That's something that everyone can enjoy.

Site Compatibility

With the release of Opera 8.5, we answered one of the biggest complaints from our users: Opera wasn't free. Since then, we've been focusing on the second biggest complaint: site compatibility. In the interest of stability, Opera hasn't seen many rendering engine fixes since Opera 9.0 was released over a year ago. That's about to change in a big way. We've fixed thousands of bugs in our rendering engine and we'll be delivering those fixes to you on Tuesday. There's still a lot more that we're planning to do and some messes to clean up, so expect to see continued progress on the rendering engine throughout the alpha and beta phases.

Some site compatibility issues can be solved by adding new functionality. That's why Kestrel includes support for things like the "overflow-x" and "overflow-y" CSS properties, JavaScript Getters and Setters, and line-/block-breaking in rich text editors. We've also fixed problems seen at Google's sites, in the default WordPress template, and in various JavaScript libraries. Opera is a web browser, after all, and Kestrel can handle more sites, better and faster than ever before.

Accessibility

Since support for screenreaders was removed in Opera 7, we've had our attention on other features. With Kestrel, we're bringing our focus back to accessibility. Kestrel includes experimental support for screenreaders such as Window-Eyes, Jaws, and VoiceOver on OS X. We're also working on support for ARIA (Accessible Rich Internet Applications from the W3C). We're happy that once again users with visual disabilities can use Opera. Special thanks to Aaron Leventhal from IBM and GW Micro (makers of Window-Eyes) for their valuable feedback.

Our work on accessibility doesn't stop with screenreader support. We've improved spatial navigation and made keyboard shortcuts more accessible for new users. There will be some significant changes in existing keyboard shortcuts, but hopefully this will be the last major refactoring we do. Many users have run into problems inadvertently making changes via single-key shortcuts, so all single-key shortcuts (such as 1/2 to switch tabs, Z/X to navigate history, etc.) are disabled by default. They can easily be re-enabled in the Preferences.

OS Integration

Though Opera is a cross-platform browser, we try to make it feel at home on each platform. This work continues in Kestrel. Opera now works better on Vista, and integrates better with Default programs dialog on XP and Vista. On OS X, Opera looks and feels more like a native OS X application, with improved tabs, better default fonts, and pulsing buttons. We're releasing 64-bit builds for the first time, so Opera will work on 64-bit FreeBSD and Linux systems without work-arounds. Furthermore, Opera does a better job handling default applications on all platforms.

Opera Mail

Opera Mail is long overdue for an overhaul and you'll see the initial stages of that overhaul in Kestrel. As previously mentioned, we've rewritten the indexing and storage back-ends, but that's not all. Kestrel also includes a new IMAP back-end that solves problems when working with multiple clients, supports hierarchical mailbox display, and fixes various other problems. The Mail panel has been refreshed and we've improved draft message handling. Opera Mail is now more stable, faster, and less buggy. The initial release will have some rough edges, but we'll be smoothing things out as we approach the final release of Kestrel.

Much More

Some of the most exciting changes in Kestrel haven't been mentioned yet, so there's still plenty to look forward to next week. Join us in #weekly to discuss Kestrel, enjoy the weekend, and rest up because the race toward Kestrel final starts Tuesday!