Firefox 附加组件兼容性

Firefox 51 附加组件兼容性：

Firefox 51 will be released on January 24th. Note that the scheduled release on December 13th is a
point release, not a major release, hence the much longer cycle. Here’s
the list of changes that went into this version that can affect add-on
compatibility. There is more information available in Firefox 51 for Developers, so you should also give it a look.

General

• Let accel-click and middle-click on the new tab button open a new tab next to the current one. This changes the behavior of the new tab button and removes the BrowserOpenNewTabOrWindow function.
• Code executed in wrong order with setTimeout after alert. This changes the behavior of the onButtonClick function to make it async.
• Drop the prefixed version of visibility API. This removes mozVisibilityState and mozHidden.
• Don’t dispatch close event, and remove onclose.
• Prevent installation of an extension when “*” is used as part of strict_min_version in a WebExtension manifest.json). Minimum versions should always be specific versions, rather than a mask.
• Loaded-as-data XML documents should not generate <parsererror>. Some add-ons are relying on this node showing up if an XML document fails to parse.

XPCOM and Modules

• Default to the NullPrincipal rather than SystemPrincipal for Favicons. This changes the functions setAndFetchFaviconForPage and replaceFaviconDataFromDataURL. The principal should generally be passed as an argument.
• Upload setting wrong Content-Type for files if you downloaded from a server that provided the wrong Content-Type. As explained in comment #36, the way add-ons change the MIME type mappings is now different, via a category rather than directly changing mimeTypes.rdf.
• Remove the last references to Actor/FrontClass. While both of these still work for add-ons, they should be considered as deprecated.

New!

• Embedded WebExtensions.
   You can now embed a WebExtension into any restartless add-on, allowing
  you to gradually migrate your code to the new platform, or transition
  any data you store to a format that works with WebExtensions.
• WebExtension Experiments. This is a mechanism that allows us (and you!) to prototype new WebExtensions APIs.

https://blog.mozilla.org/addons/2016/10/13/compatibility-for-firefox-51/

Firefox 52 附加组件兼容性：
https://blog.mozilla.org/addons/2016/12/15/compatibility-for-firefox-52/


Firefox 52 will be released on March 7th. Here’s the list of changes that went into this version
that can affect add-on compatibility. There is more information
available in Firefox 52 for Developers, so you should also give it a look.

General

• Remove support for all NPAPI plugins (except Flash). Read this blog post for more information.
• DnD of multiple shortcuts from desktop only opens one. This enables drag and drop of multiple links to the browser area, which includes some changes like replacing browserDragAndDrop.drop with browserDragAndDrop.dropLinks.
• The ChromeFilePropertyBag versions of the File constructors are web-observable. This replaces the File constructors with the static functions CreateFromFileName and CreateFromNsIFile.
• Drag and Drop: DataTransfer.types is wrong type. Instead of
   dataTransfer.types.contains, add-ons should use dataTransfer.types.includes. A shim was added to preserve compatibility, but it’s temporary.
• Crash with Youtube Subtiltle Downloader. This change makes CORS requests from add-ons using an expanded principal not work.
• Deprecate and remove CanvasRenderingContext2D.mozDash/mozDashOffset.
• Remove web content access to Battery API.

XPCOM and Modules

• Delete toolkit/obsolete. There are some utility objects there used by older add-ons, like
   nsPreferences in nsUserSettings.js and the string bundle functions in strres.js.
• Mark nsISupportsArray, nsICollection, nsIEnumerator as deprecated. These interfaces, particularly nsISupportsArray, are used in many components add-ons use. They are being replaced with nsIArray:Remove nsISupportsArray usage from nsIDragService.
• Convert inIDOMUtils.getCSSStyleRules to nsIArray.
• Use nsIArray for URL window argument.
• Remove nsISupportsArray usage from nsITransferable and nsIFormatConverter.

ImageDocument::ImageResizingEnabled is unused.

Themes

• Remove support for obsolete -moz-images-in-menus and -moz-images-in-buttons media queries.

Firefox 53.0 附加组件兼容性：
https://blog.mozilla.org/addons/2017/02/28/compatibility-for-firefox-53/



General

• Remove support for multi-package xpis.
   This is still used by a few add-ons that mix complete themes and
  extensions in a single package, but it’s going away along with other
  legacy add-on technologies.
• Use a separate content process for file:// URLs. This slightly changes the behavior of _openURIInNewTab.
• Remove support for -moz-calc().
• dom-storage2-changed notifications are not useful for private windows. This created a separate dom-private-storage2-changed notification for private windows.
• Remove unused bindings from urlbarbindings.xml. Removes <splitmenu> and <menuitem-tooltip>.
• Move content vs. content-primary distinction out of the type browser attribute.  This means type="content-primary" now works exactly as type="content", and will be dropped eventually.
• MimeTypeArray should have unenumerable named properties.
• PluginArray and Plugin should have unenumerable own properties.

Password Manager


The 3 following changes are related, and the main impact is that add-ons can no longer call findSlotByName("") to figure out if the master password is set. You can find an example on how to change this here.

• Disallow empty token names as the argument to nsIPK11TokenDB.findTokenByName.
• Add nsIPK11Token.hasPassword to replace unnecessary uses of nsIPKCS11Slot.status.
• Remove token choosing functionality from changepassword.(js|xul).

XPCOM and Modules

• Don’t expose the NSS certificate nickname API in PSM interfaces. This changes a number of methods in nsIX509Cert: addCert, addCertFromBase64, findCertByNickname, findEmailEncryptionCert, findEmailSigningCert.
• AddonManager APIs should try to support both callbacks and promises. This makes the callback for getInstallForURL to be called asynchronously.
• Remove getURIForKeyword API. PlacesUtils.keywords.fetch should be used instead.
• Support ServoStyleSheets in nsIStyleSheetService::PreloadSheet. This changes the return type of preloadSheet, which shouldn’t affect you unless you do anything other than pass it to addSheet.

WebExtensions

• Encrypt record deletes. The storage.sync API hasn’t shipped yet, but it’s probably already in use by some
  pre-release users. This change causes old synced data to be lost.

Firefox 54 附加组件兼容性：
https://blog.mozilla.org/addons/2017/04/05/compatibility-firefox-54/


General

• Remove -moz-appearance. This doesn’t apply to CSS sheets loaded using a chrome:// URL, but it does affect inline CSS styles in XUL and JavaScript code.

XPCOM and Modules

• Remove nsIFormHistory2.
• Don’t allow empty host name for URLTYPE_AUTHORITY URLs. This affects add-ons that use nsIContentPolicy to redirect certain requests (a practice that isn’t recommended, but some add-ons are known to use it).
• Remove token arguments from nsIX509CertDB.importPKCS12File and exportPKCS12File.

WebExtensions

• Implement runtime.onMessageExternal/onConnectExternal. Quoting comment 34, this changes the meaning of the browser.runtime.id property, which may cause issues for extensions which expect that to be the same as the ID used in their URLs.
• webRequest doesn’t check host permissions. You’ll need to add the necessary permissions for webRequest to continue working. At the moment this is incompatible with the Chrome API.

Firefox 55 附加组件兼容性：


General


Recently, we turned on a restriction on Nightly that only allows multiprocess add-ons to be enabled. You can use a preference to toggle it. Also, Firefox 55 is the first version to move directly from Nightly to Beta after the removal of the Aurora channel.

• Lazily load built-in SDK modules.
   The main change of this bug that could affect developers is that Panel views are loaded when the panel is first shown, rather than when it is created.
• Remove Java Addons support from Fennec.
• Replace the sNextTabParent setup with something more robust. This mainly affected tab add-ons that use or override openURIInFrame and related functions.
• Remove the hiddenwindow special case in CheckLoadURIWithPrincipal. This could affect some add-ons that use the hidden DOM window hack. See comment 11 for details.
• Get rid of UIEvent.isChar because no other browsers support it.
• Disable loading remote jars by default.
• Expose result principal URL (“final channel URL”) on LoadInfo.
   This can affect add-ons that load custom URLs using special protocols (like about:). As you can see if you follow the link, the bug was reopened. Now the developers are considering alternatives to avoid add-on issues.

XPCOM and Modules

• Move favicons blobs out of places.sqlite to their own database. This change touches many interfaces, but most adds an optional preferred width argument to some functions (see 1 and 2).
• Remove nsIScreenManager.systemDefaultScale.
• Compile subscript loader scripts with noScriptRval by default. loadSubScript no longer returns a value.
• Avoid using NSS Base64 functions in PSM. This can affect add-ons that use nsICryptoHash or nsICryptoHMAC. See comment 8 for details.

https://blog.mozilla.org/addons/2017/05/16/compatibility-firefox-55/

Firefox 56 附加组件兼容性：https://blog.mozilla.org/addons/2017/07/18/compatibility-firefox-56/


Compatibility changes

• Remove window.showModalDialog.
• Convert remaining XUL DOM classes to WebIDL. This could affect add-ons that do things like t instanceof aWindow.XULControllers, which should be rare.
• Replace uconv with encoding_rs. This could cause problems if you’re using converter services to convert to UTF-16. Comment 121 explains a little more.
• Change nsStandardURL‘s internal hostname representation to punycode. This could cause some breakage when manipulating hostnames that use non-ASCII characters.
  

Let me know in the comments if there’s anything missing or incorrect on these lists. We’d like to know if your add-on breaks on Firefox 56.The automatic compatibility validation and upgrade for add-ons on AMO will run in a few weeks, so keep an eye on your email if you have an add-on listed on our site with its compatibility set to Firefox 55.

Last stop!



Firefox 56 will be the last version of Firefox to support legacy add-ons. It’s the last release cycle you’ll have to port your add-ons to WebExtensions. Many planned APIs won’t make the cut for 57, so make sure that you plan your development timeline accordingly.
This is also the last compatibility overview I’ll write. I started writing these 7 years ago, the first one covering Firefox 4. Looking ahead, backwards-incompatible changes in WebExtensions APIs should be rare. When and if they occur, we’ll post one-offs about them, so please keep following this blog for updates.

Firefox 56 附加组件兼容性：
https://blog.mozilla.org/addons/2017/08/10/webextensions-firefox-56/