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 responses

  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.