Opera Dragonfly is a web development tool that has been integrated into the Opera web browser from Opera versions 9.5 through 12.18, similar to Mozilla Firefox and Google Chrome. It supports debugging JavaScript, viewing the DOM, monitoring network traffic, previewing resources, editing colors, etc. It also supports remote debugging, which allows using the features of Dragonfly to be used when debugging a mobile phone, TV, or another desktop computer. Opera Dragonfly must be downloaded on first use, and functions offline thereafter. Opera Dragonfly automatically updates to the latest version available, when connected to the Internet. Opera Dragonfly is compatible with Presto 2.1 and later, specifically Opera Mobile 9.5 and above, Opera Desktop 9.5 and above, and Nintendo DS & Nintendo DSi Browser.
Development of Opera Dragonfly started in May 2008. When the development started Opera Dragonfly was using the BSD license, but later it was changed to the Apache License 2.0. On 21 September 2011, the Opera Dragonfly team announced that it would be more focused on individual components, eg the DOM inspector or the UI framework. As soon as a feature has been implemented, it would be possible for the experimental path for some initial testing. As part of the new release strategy, they switched over to Opera Dragonfly to a new version scheme: <major-version>. . . <today’s-build> Inclusion of Dragonfly Opera ended after Opera 12.x, when Opera switched from the Presto layout engine to Blink and Chromium based. Subsequent versions included Chromium’s DevTools instead. As of 2015,