Firefox 14 for developers

• The <progress> element is no longer incorrectly classified as a form element, and therefore no longer has a form attribute.
• The default modifier keys for the accesskey of HTML contents on Mac are changed to Control+Option. This is the same as WebKit-based browsers on Mac.

• input events are fired also on editing host element of contenteditable editor and root element of designMode editor.
• DOMException.code is now deprecated per latest DOM Level 4 specification.
• The Range.insertNode() method now works correctly when used on collapsed ranges.
• The MozBlobBuilder interface has been deprecated in favor of the constructor on Blob. If you use MozBlobBuilder you'll see a warning message in the Web Console.
• The Blob() constructor is now available to workers (Firefox bug 736686).
• Support for the Mutation Observers has been landed. It is designed as a replacement for the Mutation Events in DOM3, which has a number of issues regarding performance.
• The HTMLImageElement interface's x and y properties were removed in Firefox 7.0 but restored in this release for compatibility reasons.
• The Document methods execCommandShowHelp() and queryCommandText(), which never did anything, have been removed.
• The GeoPositionAddress interface, an obsolete part of the Geolocation API, has been removed.
• localStorage/sessionStorage now correctly return undefined instead of null for undeclared keys through property access.ff
• The ImageData object has been implemented (Firefox bug 550309).
• Attributes and methods related to child nodes on Attr interface were obsoleted (Firefox bug 737122).

• The text-transform and font-variant CSS properties have been fixed to correctly handle the i → İ and ı → I Turkic-specific case pairs.
• The Dutch IJ digraph is now correctly handled by text-transform: capitalization. Similarly the Greek letter Σ, which has two lowercase forms, σ and ς, is now correctly handled by text-transform: lowercase.
• Support for the skew() function has been removed from transform property, as it has been removed from the draft standard.
• The syntax for border-image has been updated to match the latest revision of the specification; it no longer accepts a trailing slash ("/").

No change.

• The syntax of the statusline action type on <maction> elements has been adjusted to follow the MathML specification.

• Gecko now supports the new HTTP 308 Permanent Redirect status code. As Gecko doesn't make a distinction between permanent and temporary redirects, it behaves like the 307 Temporary Redirect status code, as it forbids the user agent from changing the HTTP method used between the two requests (POST will stay POST, GET will stay GET).

source-editor.jsm

• Added a keyboard shortcut to toggle commenting for the current selection (Ctrl-/ or Cmd-/ on Mac OS X).
• Added the Ctrl-[ and Ctrl-] keyboard shortcuts for moving the text input position to the beginning and end of the current block.
• Added the new getLineStart() and getLineEnd() methods.

• Added the new fullscreenbutton attribute to the <window> element; setting this to true adds a button to the window's chrome to enable full screen mode.

• The nsILocalFile interface has been merged into nsIFile (bug 682360).
• The methods in nsIPlacesImportExportService for importing bookmarks have all been removed in favor of the BookmarkHTMLUtils.jsm JavaScript code module.
• The nsIDOMGeoPositionAddress interface has been removed.
• The getItemGUID, setItemGUID and getItemIdForGUID methods have been removed from nsINavBookmarksService (Firefox bug 715355).

• Dictionary names are now parsed as full BCP 47 language tags (bug 730209, bug 741842). Developers are encouraged to not hard-code the name of their language in their dictionary names.