Firefox 68 pour développeurs

Cet article fournit des informations à destination des développeurs à propos des changements dans Firefox 68. Firefox 68 a été lancée le 9 Juillet 2019.

Changements pour développeurs web

Outils développeur

  • La console web montre maintenant plus d'informations à propos des warnings CSS, ceci inclut la liste de noeuds des éléments du DOM qui utilisaient la règle (bug 1093953).
  • Vous pouvez maintenant filtrer du contenu dans la console Web en utilisant des expressions régulières (REGEX) (bug 1441079).
  • La console du navigateur vous permet maintenant de montrer ou cacher les messages provenant du processus de contenus en paramètrant ou vidant la checkbox intitulé Show Content Messages (bug 1260877).

Le débuggeur JavaScript

  • Vous pouvez maintenant Rechercher dans tout les fichiers du projet en cours depuis le débuggeur en appuyant sur les touches Shift + Ctrl + F (Windows ou Linux) ou Shift + Cmd + F (macOS) (bug 1320325).

Le moniteur réseau

  • La liste des requêtes du moniteur réseau vous permet maintenant de bloquer une URL spécifique (bug 1151368).
  • Vous pouvez maintenant ré-envoyer une requête réseau sans éditer la méthode HTTP, l'URL, les paramètres et les en-têtes, en utilisant la commande Ré-envoyer dans le menu contextuel (bug 1422014).
  • L'onglet en-têtes du menu contextuel du moniteur réseau vous permet maintenant de copier tout ou une partie de l'information de l'en-tête dans le presse-papier au format JSON (bug 1442249).

L'inspecteur de styles et du DOM

  • Un bouton qui vous permet de basculer l'affichage de n'importe quels media queries a été ajouté dans le panneau des règles de l'inspecteur (bug 1534984).
  • Le panneau de polices de caractère inclut maintenant un bouton glissoire pour modifier l'espacement des lettres letter-spacing (bug 1536237).
  • Une icône d'alerte apparaît à côté des propriétées CSS non supportées et des règles ayant des valeurs invalides, pour vous aider à comprendre pourquoi certains styles ne sont pas appliqués (bug 1306054).

Storage inspector


  • The Accessibility Inspector now includes a new Check for issues feature, which will include a number of audit tools to highlight accessibility problems on your web pages. The first available check is contrast, for highlighting color contrast problems.
  • The preference that controls the visibility of internal extensions (system add-ons and hidden extensions) on the about:debugging page has been changed from devtools.aboutdebugging.showSystemAddons to devtools.aboutdebugging.showHiddenAddons (bug 1544372).
  • Responsive design mode has been redesigned — the Device Settings dialog (device selection menu > Edit List...) is now more intuitive and simpler to use (bug 1487857).



  • The <track> element — represented by HTMLTrackElement — now receives a cuechange event in addition to the TextTrack itself, if the text track is a contained by a media element (bug 1548731).
  • <link> elements support the disabled attribute again, albeit with different behavior. When disabled is set on a <link> element along with rel="stylesheet", the referenced stylesheet is not loaded during page load, and will be loaded on demand when the disabled attribute is changed to false or removed (bug 1281135).





No changes.



CSS Object Model (CSSOM)

  • The legacy rules property and addRule() and removeRule() methods have been added to the CSSStyleSheet interface. These were introduced by Internet Explorer 9 and have never managed to quite be stamped out, so they have been added to improve compatibility with the small percentage of sites that still use them (bug 1545823).


DOM events

  • Firefox for Android no longer incorrectly sends a resize event until after the first frame is painted; this improves web compatibility with sites that don't expect this event to occur (bug 1528052).
  • The dispatching of events for non-primary mouse buttons has been made to more closely follow the specification; the click event is no longer sent when non-primary buttons are clicked, instead using auxclick. In addition, dblclick no longer fires for non-primary buttons (bug 1379466).
  • The proprietary MouseEvent.mozPressure property has been deprecated, and will now trigger a warning in the console (bug 1165211).

Media, Web Audio, and WebRTC

  • Due to changes in the Google Play store's policies, starting with Firefox 68 for Android, the OpenH264 codec used to handle AVC/H.264 video in WebRTC connections can no longer be downloaded and installed. Therefore, fresh installs of Firefox on Android devices no longer support AVC in WebRTC calls. If you upgrade from earlier versions of Firefox and already have the codec downloaded, it will continue to work. This does not affect other platforms. For more details, see this article on SUMO or bug 1548679.
  • WebRTC has been updated to recognize that a null candidate passed into the icecandidate event handler, indicating the receipt of a candidate, instead indicates that there are no further candidates coming; when this happens the ICE gathering (iceGatheringState) state reaches complete (bug 1318167).
  • The RTCRtpReceiver methods getContributingSources() and getSynchronizationSources() now support video tracks; previously they only worked on audio (bug 1534466).
  • The Web Audio API MediaStreamTrackAudioSourceNode interface is now supported, as is the method AudioContext.createMediaStreamTrackSource() (bug 1324548).
  • RTCDataChannel.negotiated is now implemented (bug 1529695).
  • The MediaStreamAudioSourceNode() constructor has been updated to match the current specification's definition that the "first audio track" in the stream is the track whose ID comes first in lexicographical order (bug 1324548).
  • getUserMedia() may no longer be used from a non-secure context; attempting to do so now throws a NotAllowedError exception. Secure contexts are those loaded using HTTPS, those located using the file:/// scheme, and those loaded from localhost. For now, if you must, you can re-enable the ability to perform insecure calls to getUserMedia() by setting the preference media.getusermedia.insecure.enabled to true (bug 1335740).

    Note: In the future, Firefox will also remove the navigator.mediaDevices property on insecure contexts, preventing all access to the MediaDevices APIs. This is already the case in Nightly builds.



  • The HTTP Clear-Site-Data header no longer supports the executionContexts directive. This was removed due to problems with interactions between interconnections among different kinds of data at different points in the navigation process and the way the specification is designed. It has been proposed that this directive be removed from the specification for this reason, among others (bug 1548034).


  • The Content-Security-Policy directive require-sri-for is no longer supported due to concerns about its standardization status. It was previously available only behind a preference, which was off by default (bug 1386214).


WebDriver conformance (Marionette)

Bug fixes

  • If WebDriver:SwitchToWindow changes the selection to a different window it now waits for its focus and activate events before returning (bug 1335085).
  • Fixed the TypeError: this.tabModal is null failure, which sometimes appeared when interacting with modal dialogs or user prompts (bug 1538782)


  • Disabled the feature to force unloading background tabs on low memory conditions, to prevent top-level browser contexts from magically disappearing (bug 1553748).
  • Disabled priviledged content processes that caused HTTP authentication dialogs not to appear when navigating to a website after opening a new tab (bug 1558763).


No changes.

Changes for add-on developers

API changes

  • The The proxy.register() and proxy.unregister() functions have been deprecated and will be removed from Firefox 71 (bug 1545811).
  • A boolean flag, incognito, has been added to the proxy.RequestDetails. object. When true, it indicates that this was a private browsing request (bug 1545163).
  • The webRequest.RequestFilter parameters can include an incognito parameter. If provided, requests that do not match the incognito state (true or false) will be filtered out (bug 1548177).
  • A string value, cookieStoreId, representing the cookie store ID of the current context, has been added to the proxy.RequestDetails. object (bug 1545420).
  • When an add-on attempts to add a bookmark folder to the root folder, the resulting error message is now much more intuitive (bug 1512171).
  • The promise returned by browser.tabs.duplicate() now resolves immediately, before the tabs are completely loaded (bug 1394376).
  • Support has been added for, allowing web extension settings to be implemented via enterprise policy (bug 1230802).

Manifest changes

No changes.

See also

Older versions