2011
Opera Dragonfly - Style profiler preview
As a real world example of how big the impact can be on performance, I made a test with the full HTML5 specification downloaded locally and ran the profiler. I noticed few of the most expensive selectors had ":link" and ":visited". I changed these to instead be "a:link" or "a:visited" (in this case they were equivalent in terms of which elements matched). This trivial change makes the engine use a cache, and bought the selector matching time down from about 14 seconds to about 11 seconds.
2008
Opera Dragonfly
by marco & 7 others
Opera's upcoming Developer Tools. Debug JavaScript, inspect CSS and the DOM, and view any errors
Opera Dragonfly
by Xavier Lacot & 7 others
Welcome to Opera Dragonfly alpha, the foundations of Opera's upcoming Developer Tools. Debug JavaScript, inspect CSS and the DOM, and view any errors – Opera Dragonfly makes developing using Opera easier than ever, both on your computer and mobile phone.
Introduction to Opera Dragonfly
by Xavier Lacot & 3 others
We have unleashed the Dragonfly! Opera Dragonfly is Opera's all-new set of developer tools, designed to give developers a lightweight-but-powerful application that provides effective mechanisms for web standards debugging and problem solving without slowing down the browser, and fits in nicely with the development workflow.
