Changes for Web developers

Developer Tools

Highlights:

All devtools bugs fixed between Firefox 30 and Firefox 31.

CSS

  • Changed var- prefix of CSS Variables to -- to reflect the final spec change (bug 985838).
  • The hyphens property now support Polish hyphenation rules (bug 987668).
  • Removed an unwanted white space for multiple of 10,000 in Korean counter styles (bug 985186).
  • CSS opacity transition broken with parent pseudo :before and overflow auto (bug 990340).
  • The ::-moz-math-stretchy pseudo-element has been removed (bug 1000879).

HTML

JavaScript

New ECMAScript 6 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:
    #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.

See also

Older versions

Document Tags and Contributors

Last updated by: Sebastianz,