Firefox 24 for developers

  • Revision slug: Mozilla/Firefox/Releases/24
  • Revision title: Firefox 24 for developers
  • Revision id: 470059
  • Created:
  • Creator: derobert
  • Is current revision? No
  • Comment

Revision Content

This page is not complete
It hasn't been fully updated since Firefox 24 released.

{{ ReleaseChannelInfo("24", "24", "September 2013", "Beta") }}

Want to help document Firefox 24? See the list of bugs that need to be written about and pitch in!

Changes for Web developers

CSS

  • The two values -moz-zoom-in and -moz-zoom-out of the {{cssxref("cursor")}} property have been unprefixed to zoom-in and zoom-out ({{bug("772153")}}).

HTML

  • The {{HTMLElement("track")}} element has been implemented behind the media.webvtt.enabled property ({{bug(833385)}}).

JavaScript

  • Arrow functions are no longer automatically in strict mode unless explicitly requested with "use strict" ({{bug(852762)}}).
  • The String.prototype.repeat JS method has been implemented ({{bug(815431)}}).

DOM

  • Support for the {{domxref("Range.Range", "Range()")}} constructor has been added ({{bug(868999)}}).
  • Support for the {{domxref("Text.Text", "Text()")}} constructor has been added ({{bug(869000)}}).
  • Support for the {{domxref("Comment.Comment", "Comment()")}} constructor has been added ({{bug(869006)}}).
  • Support for the {{domxref("DocumentFragment.DocumentFragment", "DocumentFragment()")}} constructor has been added ({{bug(869002)}}).
  • The {{domxref("FocusEvent")}} interface has been implemented ({{bug(855741)}}).
  • Support for the {{domxref("ChildNode.remove()")}} method has been added ({{bug(856629)}}).
  • The interfaces related to the {{HTMLElement("track")}} element, {{domxref("HTMLTrackElement")}}, {{domxref("TextTrack")}}, {{domxref("TextTrackCue")}}, {{domxref("TextTrackList")}}, and {{domxref("TextTrackCueList")}} have been implemented behind the media.webvtt.enabled property, defaulting to false ({{bug(833385)}}).
  • The {{domxref("Gamepad")}} interface, and {{domxref("Navigator.getGamepads")}} have been implemented behind the dom.gamepad.enabled property, defaulting to false ({{bug(690935)}}).
  • On desktop Firefox only, HTMLCanvasElement.getContext() can now take the webgl value, in addition to experimental-webgl ({{bug(870232)}}).
  • The non-standard method mozLoadFrom() of {{domxref("HTMLMediaElement")}} has been removed ({{bug(877135)}}).

Developer Tools

  • The Network inspector now lets you filter by content type (CSS/image/font etc.) and see the relevant size and load times.
  • The Devtools options panel to the left lets you disable/enable Javascript temporarily.
  • Extension developers may use the new Browser Console for Chrome-level scripts (Replaces Error Console).

See also

Older versions

{{Firefox_for_developers('23')}}

Revision Source

<div class="overheadIndicator draft draftHeader">
  <strong>This page is not complete</strong>
  <div>
    It hasn't been fully updated since Firefox 24 released.</div>
</div>
<p>{{ ReleaseChannelInfo("24", "24", "September 2013", "Beta") }}</p>
<p>Want to help document Firefox 24? See the <a class="external" href="http://beta.elchi3.de/doctracker/#list=fx&amp;version=24.0">list of bugs that need to be written about</a> and pitch in!</p>
<h2 id="Changes_for_Web_developers">Changes for Web developers</h2>
<h3 id="CSS">CSS</h3>
<ul>
  <li>The two values <code>-moz-zoom-in</code> and <code>-moz-zoom-out</code> of the {{cssxref("cursor")}} property have been unprefixed to <code>zoom-in</code> and <code>zoom-out</code> ({{bug("772153")}}).</li>
</ul>
<h3 id="HTML">HTML</h3>
<ul>
  <li>The {{HTMLElement("track")}} element has been implemented behind the <code>media.webvtt.enabled</code> property ({{bug(833385)}}).</li>
</ul>
<h3 id="JavaScript">JavaScript</h3>
<ul>
  <li><a href="/en-US/docs/Web/JavaScript/Reference/arrow_functions" title="/en-US/docs/Web/JavaScript/Reference/arrow_functions">Arrow functions</a> are no longer automatically in strict mode unless explicitly requested with <code>"use strict"</code> ({{bug(852762)}}).</li>
  <li>The <a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/repeat" title="/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/repeat"><code>String.prototype.repeat</code></a> JS method has been implemented ({{bug(815431)}}).</li>
</ul>
<h3 id="DOM">DOM</h3>
<ul>
  <li>Support for the {{domxref("Range.Range", "Range()")}} constructor has been added ({{bug(868999)}}).</li>
  <li>Support for the {{domxref("Text.Text", "Text()")}} constructor has been added ({{bug(869000)}}).</li>
  <li>Support for the {{domxref("Comment.Comment", "Comment()")}} constructor has been added ({{bug(869006)}}).</li>
  <li>Support for the {{domxref("DocumentFragment.DocumentFragment", "DocumentFragment()")}} constructor has been added ({{bug(869002)}}).</li>
  <li>The {{domxref("FocusEvent")}} interface has been implemented ({{bug(855741)}}).</li>
  <li>Support for the {{domxref("ChildNode.remove()")}} method has been added ({{bug(856629)}}).</li>
  <li>The interfaces related to the {{HTMLElement("track")}} element, {{domxref("HTMLTrackElement")}}, {{domxref("TextTrack")}}, {{domxref("TextTrackCue")}}, {{domxref("TextTrackList")}}, and {{domxref("TextTrackCueList")}} have been implemented behind the <code>media.webvtt.enabled</code> property, defaulting to <code>false</code> ({{bug(833385)}}).</li>
  <li>The {{domxref("Gamepad")}} interface, and {{domxref("Navigator.getGamepads")}} have been implemented behind the <code>dom.gamepad.enabled</code> property, defaulting to <code>false</code> ({{bug(690935)}}).</li>
  <li>On desktop Firefox only, <code>HTMLCanvasElement.getContext()</code> can now take the <code>webgl</code> value, in addition to <code>experimental-webgl</code> ({{bug(870232)}}).</li>
  <li>The non-standard method <code>mozLoadFrom()</code> of {{domxref("HTMLMediaElement")}} has been removed ({{bug(877135)}}).</li>
</ul>
<h3 id="Developer_Tools">Developer Tools</h3>
<ul>
  <li>The Network inspector now lets you filter by content type (CSS/image/font etc.) and see the relevant size and load times.</li>
  <li>The Devtools options panel to the left lets you disable/enable Javascript temporarily.</li>
  <li>Extension developers may use the new <a href="http://www.robodesign.ro/mihai/blog/the-browser-console-is-replacing-the-error-console" title="http://www.robodesign.ro/mihai/blog/the-browser-console-is-replacing-the-error-console">Browser Console</a> for Chrome-level scripts (Replaces Error Console).</li>
</ul>
<h2 id="See_also">See also</h2>
<ul>
  <li><a href="http://www.mozilla.org/en-US/firefox/24.0a2/auroranotes/">Firefox 24 Aurora Notes</a></li>
  <li><a href="/en-US/docs/Site_Compatibility_for_Firefox_24">Site Compatibility for Firefox 24</a></li>
</ul>
<h3 id="Older_versions">Older versions</h3>
<p>{{Firefox_for_developers('23')}}</p>
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