Firefox 31 附加组件兼容性

Firefox 31 will be released on July 22nd. Here’s the list of changes that went into this version
that can affect add-on compatibility. There is more information
available in Firefox 31 for Developers, so you should read that too.

General

• Remove the browser.tabs.closeButtons pref. This pref used to determine if there should be close buttons per tab, only on the active tab, or at the end of the tab bar.
• getShortcutOrURIAndPostData should have a synchronous callback behavior. Instead of returning a promise, now it takes a second callback argument.
• Warn about XMLHttpRequest sendAsBinary usage.
   This is only a warning, but you should consider this function to be
  deprecated. There are various other ways to send binary data, like
  setting the content type header or using a Blob.
• Simplify conditional forward button CSS by making the forward button a direct sibling of the location bar. This might interest theme developers.

Content

• Hide DataContainerEvent from content. MessageEvent or CustomEvent can be used instead.
• Stop exposing BrowserFeedWriter to the Web.

XPCOM

• Add a dedicated API to provide a final complete value different from the matching one. If you implement an autocomplete provider in your extension, you will need to add a new function called getFinalCompleteValueAt. There are examples of this in this MDN article.
• Remove the state string from sessionstore-state-write.

New!

• Ship CSS Variables (that is, enable the preference). More info about CSS Variables on MDN.
• Add a Log.Logger API for logging exceptions/errors.

Please let me know in the comments if there’s anything missing or
incorrect on these lists. If your add-on breaks on Firefox 31, I’d like
to know.
The automatic compatibility validation and upgrade for add-ons on AMO
 will happen soon, so keep an eye on your email if you have an add-on
listed on our site with its compatibility set to Firefox 30.