Add-on Compatibility for Firefox 34

Firefox 34 will be released on November 25th. Here’s the list of changes that went into this version that can affect add-on compatibility. There is more information available in Firefox 34 for Developers, so you should also give it a look.




  • Import and use public domain JNI.jsm implementation. This is a useful module for Android add-on developers that need low-level access. It has been renewed with a more complete implementation. You can get the module with Components.utils.import("resource://gre/modules/JNI.jsm");

Please let me know in the comments if there’s anything missing or incorrect on these lists. If your add-on breaks on Firefox 34, 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 33.

10 comments on “Add-on Compatibility for Firefox 34”

  1. Kohei Yoshino wrote on

    Japanese translation:

  2. Andres Ruiz wrote on

    I really think its been some time that Firefox hasn’t had a compatible Spanish (Mexico) language pack with resent versions. is would be very useful if it was. I’m not sure if this the right place or procedure but I don’t have the time to register on the add-on forum.
    Thank you

    1. Jorge Villalobos wrote on

      It looks like this one is kept up to date.

  3. matt mcccarty wrote on

    how can i keep track of all my apps on my phone

  4. bdhr wrote on

    > If your add-on breaks on Firefox 34, I’d like to know.

    My extension (not on AMO, but on the BitBucket page linked to my name*) works** in Fennec 33.1 but not in 34.

    It installs and the preferences are available but the changes I make to the DOM in my pagemods don’t take effect.

    I get errors like these in logcat:

    E/GeckoConsole( 1273): [JavaScript Error: “t is not defined” {file: “resource://gre/modules/addons/XPIProvider.jsm -> jar:file:///data/data/org.mozilla.firefox/files/mozilla/orxe1i7e.default/extensions/jid0-xABZkhS0Qpa6BSx8QQu15jrIUUk@jetpack.xpi!/bootstrap.js -> resource://gre/modules/commonjs/toolkit/loader.js -> resource://gre/modules/commonjs/sdk/windows/tabs-fennec.js” line: 162}]

    E/GeckoConsole( 1273): [JavaScript Error: “[Exception… “Component does not have requested interface” nsresult: “0x80004002 (NS_NOINTERFACE)” location: “JS frame :: resource://gre/modules/addons/XPIProvider.jsm -> jar:file:///data/data/org.mozilla.firefox/files/mozilla/orxe1i7e.default/extensions/jid0-xABZkhS0Qpa6BSx8QQu15jrIUUk@jetpack.xpi!/bootstrap.js -> resource://gre/modules/commonjs/toolkit/loader.js -> resource://gre/modules/commonjs/sdk/tabs/utils.js :: isFennecTab :: line 42″ data: no]”]

    For reference, it works fine on desktop Firefox 34.

    If you can provide any help, I’d appreciate it.

    *In case you attempt to test it, note that by default, the extension, including the XPIs on the downloads page, doesn’t work on mobile, because I use the panel module. Right now I use the kludge of a script to strip out the panel usage temporarily, build an XPI, and add the panel back in. If there’s a way to do this at runtime instead please let me know.

    **Technically, some functionality is broken in git on Firefox < 34 because I recently started using (unprefixed) Element.matches(), but that's beside the point.

    1. bdhr wrote on

      Oh, and this is on both SDK 1.16 and 1.17.

  5. willf wrote on

    Firefox 34 broke the flashblock add-on. This is a real drag as I depend on that add-on preventing websites from draining the battery on my laptop and using up my CPU resource. As an aside, perhaps this sort of control (allowing/blocking flash from playing automatically) should be built into FIrefox? I, for one, would appreciate that.

    1. J. McNair wrote on

      It is built-in, just not easy to find. It’s also not quite as
      Firefox button -> Add-ons -> Plugins
      On the dropdown, next to Shockwave Flash, choose “Ask to Activate”

      Now, every web site with Flash will have a gray bar asking if you want to allow it. If you select “Continue blocking”, then every Flash object will have a gray box asking to activate it.

      1. willf wrote on

        I see. I guess the issue with the native flash blocking method is that it doesn’t support a whitelist of sites allowed to play flash unlike flashblock. If native flash (or other plugin) blocking supported whitelisting I’d drop flashblock.

    2. Don wrote on

      I agree. If you are on a slow connection Flash KILLS you.
      It should be a standard feature.