Facebook Container for Firefox

Firefox has a nifty extension—made by Mozilla—called Facebook Container. It does two things.

First of all, it sandboxes any of your activity while you’re on the facebook.com domain. The tab you’re in is isolated from all others.

Secondly, when you visit a site that loads a tracker from Facebook, the extension alerts you to its presence. For example, if a page has a share widget that would post to Facebook, a little fence icon appears over the widget warning you that Facebook will be able to track that activity.

It’s a nifty extension that I’ve been using for quite a while. Except now it’s gone completely haywire. That little fence icon is appearing all over the web wherever there’s a form with an email input. See, for example, the newsletter sign-up form in the footer of the Clearleft site. It’s happening on forms over on The Session too despite the rigourous-bordering-on-paranoid security restrictions in place there.

Hovering over the fence icon displays this text:

If you use your real email address here, Facebook may be able to track you.

That is, of course, false. It’s also really damaging. One of the worst things that you can do in the security space is to cry wolf. If a concerned user is told that they can ignore that warning, you’re lessening the impact of all warnings, even serious legitimate ones.

Sometimes false positives are an acceptable price to pay for overall increased security, but in this case, the rate of false positives can only decrease trust.

I tried to find out how to submit a bug report about this but I couldn’t work it out (and I certainly don’t want to file a bug report in a review) so I’m writing this in the hopes that somebody at Mozilla sees it.

What’s really worrying is that this might not be considered a bug. The release notes for the version of the extension that came out last week say:

Email fields will now show a prompt, alerting users about how Facebook can track users by their email address.

Like …all email fields? That’s ridiculous!

I thought the issue might’ve been fixed in the latest release that came out yesterday. The release notes say:

This release addresses fixes a issue from our last release – the email field prompt now only displays on sites where Facebook resources have been blocked.

But the behaviour is unfortunately still there, even on sites like The Session or Clearleft that wouldn’t touch Facebook resources with a barge pole. The fence icon continues to pop up all over the web.

I hope this gets sorted soon. I like the Facebook Container extension and I’d like to be able to recommend it to other people. Right now I’d recommed the opposite—don’t install this extension while it’s behaving so overzealously. If the current behaviour continues, I’ll be uninstalling this extension myself.

Update: It looks like a fix is being rolled out. Fingers crossed!

the Web at a crossroads - Web Directions

John weighs in on the clashing priorities of browser vendors.

Imagine if the web never got CSS. Never got a way to style content in sophisticated ways. It’s hard to imagine its rise to prominence in the early 2000s. I’d not be alone in arguing a similar lack of access to the sort of features inherent to the mobile experience that WebKit and the folks at Mozilla have expressed concern about would (not might) largely consign the Web to an increasingly marginal role.

Facebook Container Extension: Take control of how you’re being tracked | The Firefox Frontier

A Firefox plugin that ring-fences all Facebook activity to the facebook.com domain. Once you close that tab, this extension takes care of garbage collection, ensuring that Facebook tracking scripts don’t leak into any other browsing activities.

Mozilla betrays Firefox users and its nominal principles

That’s a harsh headline but it is unfortunately deserved. We should indeed hold Mozilla to a higher standard.

Monica at Mozilla: Tracking Protection for Firefox at Web 2.0 Security and Privacy 2015

I believe that Mozilla can make progress in privacy, but leadership needs to recognize that current advertising practices that enable “free” content are in direct conflict with security, privacy, stability, and performance concerns — and that Firefox is first and foremost a user-agent, not an industry-agent.