Firefox 22 Compatibility Update

About a week ago I published the Firefox 22 Add-on Compatibility post. Today I learned about a new compatibility-breaking change that could affect some add-ons, though it seems to be unlikely. I would have mentioned it in my previous post if I had known about it then, so I thought it was necessary to post this update.

nsIFilePicker crash if overriding component has not implemented a domfiles getter. This crash bug was recently filed, caused by an add-on that overrides the nsIFilePicker component. The crash appeared in Firefox 22, due to bug 832923, which changed the nsIFilePicker interface. So, if your add-on does that, you should update its implementation to make sure it includes the domfile and domfiles getters.

The crash bug will be fixed so that Firefox doesn’t crash even when faced with the interface mismatch. However, affected add-ons still won’t work correctly unless updated.

6 comments on “Firefox 22 Compatibility Update”

  1. Word Count wrote on

    My add-on automatically got upgraded to be 22 compatible. I will wait till 25th June to actually test it in the real browser.

    1. Jorge Villalobos wrote on

      You shouldn’t wait until the release date to test your add-on. It can take weeks before an update for your add-on becomes available, and that will hurt your users.

      1. Word Count wrote on

        Thank you for your heads-up. The automatic test shows that my add-on is compatible with Firefox 22. That is all I have, how can I test my add-on with Firefox 22 when it is still not available?

        1. Jorge Villalobos wrote on

          You can install Beta (future Firefox 22) and Aurora (future Firefox 23) from this page. When Firefox 22 is released, Beta will turn into 23 and Aurora into 24.

          1. Word Count wrote on

            Thank you for your tips.

    2. Susie Johnston wrote on


      I have been using Firefox for years as my preferred Browser, however today I had to switch my loyalties to IE.
      The reason for this is because Firefox continually wants me to update to a version that is not compatible with my Norton Toolbar. I have tried to find a version of Firefox that will allow me to run my computer according to MY likes and dislikes, but was unsuccessful in finding one.
      Apologies if this is the wrong arena for my comment, however I think someone linked to Firefox needs to know why you have now lost me – and according to what I have read on the subject, I am not alone.

      Susie Johnston