Firefox 31 for developers

Changes for Web developers

Developer Tools

CSS

HTML

JavaScript

New ECMAScript 2015 features implemented:

Interfaces/APIs/DOM

MathML

SVG

No change.

Audio/Video

No change.

Security

Changes for add-on and Mozilla developers

  • The "align" attribute on the urlbar-wrapper (formerly on the urlbar-container) which was set to "center" since time immemorial, has been removed. This is known to affect third-party themes. You should look carefully at what the right fix is for your theme, but for maintaining the equivalent effect, you can add the following CSS rule to your theme:
    css
    #urlbar-wrapper {
      -moz-box-align: center;
    }
    
  • nsIDOMWindowUtils.sendQueryContentEvent() and nsIDOMWindowUtils.sendSelectionSetEvent() have aAdditionalFlags as optional argument. If you called nsIDOMWindowUtils.sendSelectionSetEvent() with true for aReverse, the behavior would be broken by this change. See explanation of each flag (QUERY_CONTENT_FLAG_* and SELECTION_SET_FLAG_*) for the detail of aAdditionalFlags.

Add-on SDK

Highlights:

GitHub commits made between Firefox 30 and Firefox 31. This will not include any uplifts made after this release entered Aurora.

Bugs fixed between Firefox 30 and Firefox 31. This will not include any uplifts made after this release entered Aurora.

Older versions