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Firefox 46 was released on April 26, 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

Highlights:

All devtools bugs fixed between Firefox 45 and Firefox 46.

HTML

CSS

JavaScript

Interfaces/APIs/DOM

DOM & HTML DOM

Canvas

WebGL

IndexedDB

No change.

Service Workers

Fetch

  • Request.mode now has a new value available, navigate, for supporting requests generated while navigating between documents (see bug 1209081.)

WebRTC

  • The RTCPeerConnection.createOffer() method now supports the VP9 video codec, although this is disabled by default. To enable it, set the preference media.peerconnection.video.vp9_enabled to true in about:config. When enabled, VP9 is the preferred codec; previously VP8 was preferred (bug 1242324).

New APIs

Miscellaneous

MathML

No change.

SVG

No change.

Audio/Video

No change.

HTTP

No change.

Networking

  • Support of RFC 7686 has been added: by default there is no attempt to resolve domain with the TLD .onion. This is controlled by the preference network.dns.blockDotOnion. Add-ons supporting Tor can swap this pref. (bug 1228457)

Security

No change.

Changes for add-on and Mozilla developers

Interfaces

No change.

XUL

No change.

JavaScript code modules

No change.

XPCOM

No change.

Other

No change.

See also

Older versions

Document Tags and Contributors

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 Last updated by: Sheppy,