Privacy UI
As many of you probably know, I’ve been a big proponent of adding a private browsing mode to Firefox ever since I joined Mozilla (technically I was even advocating for the feature while in the process of interviewing here). So after two years, you can’t imagine how pleased I am to finally be doing some design work as we prepare to ship the feature. We all owe a tremendous thanks to Ehsan for his awesome work and consistent determination to get the feature implemented.
Over the last two years I’ve also humorously found myself in a few of the actual stereotypical examples that we normally use to explain the broad and diverse range of use cases for private browsing:
-I had to load up Safari to research engagement rings
-I literally had a birthday present ruined for me thanks to seeing someone else’s browsing history
Thankfully I haven’t had to research a super embarrassing medical condition yet, but at this rate that’s probably up next.
Private browsing mode is actually just one of a number of privacy improvements that we are hoping to get into Shiretoko. Some of the other changes include:
-A “Clear Recent History” dialog, which is kind of like private browsing mode, but it works in reverse (all good interfaces support undo!)
-A refreshed Privacy preference pane that allows you to control what types of information appear in the location bar’s search results, and place Firefox into a permanent state of private browsing. The redesign also addresses some of the quirky things about the previous interface.
I should note that as always, nothing is ever guaranteed to make it into the next release, and shedules and feature sets are often in a state of flux. So with that said, here is the current set of mockups:
Privacy Features in Shiretoko (or a later release)
A New Metaphor for Privacy
Since we are hoping to roll out so many features related to privacy in one release, we felt it was a good time to update the metaphor we are using to represent the concept of privacy in Firefox. The new metaphor is a masquerade mask:
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I think this makes a great icon, since it captures the concept while at the same time being recognizable, colorful, and fun. Credit for the inspired idea goes to mcdavis in a post back in May 2007 to dev.apps.firefox when we were still considering private browsing mode for Firefox 3.
Next Up: an Ambient Visual Cue
You might have noticed that there isn’t much of an indicator in the current iteration of the mockup to tell you that you are in private browsing mode. I’ll cover how we hope to provide an ambient cue (possibly in 3.2) in my next post.



When I go into an Apple Store to use their free Internet terminals, I always turn on Safari Private Browsing. I’m surprised more is not made of this use case.