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Firefox

Firefox 48 for developers

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Firefox 48 was released on August 2, 2016. This article lists key changes that are useful not only for web developers, but also Firefox and Gecko developers as well as add-on developers.

Changes for Web developers

Developer Tools

HTML

  • The <details> and <summary> elements have been activated by default on Nightly and Aurora (DevTools), but not on Beta or Release:
    • The default style for these elements has been adapted to match the spec ({{ bug }}).
    • The toggle event is now sent to the <details> element when this one is opened or closed (bug 1225412).
  • The meta attributes now also supports the no-referrer-when-downgrade and origin-when-cross-origin values (bug 1178337).

CSS

JavaScript

New APIs

Deprecations and removals

Interfaces/APIs/DOM

DOM & HTML DOM

Canvas 2D

WebRTC

Others

HTTP

Changes for add-on and Mozilla developers

See also

Older versions

Document Tags and Contributors

 Last updated by: Sebastianz,