Sunday, May 15, 2011

Clearing Flash cookies using Firefox

Back in March, we shipped Firefox 4 with a feature that sends a signal to plugins like Flash and Silverlight when you clear your cookies. Adobe has announced that starting with Flash Player version 10.3, they'll be listening to the signal! This is exciting, because clearing your flash cookies is as easy as clearing regular cookies in this latest version of flash.

Here's when Firefox 4 tells Flash Player version 10.3 to delete LSOs (Flash cookies):
  • When you clear all your cookies in Firefox using "clear recent history" [how-to link]
  • When you choose "forget about this site" in your library (history) window [how-to link]
  • When you quit Firefox, if you have Firefox configured to clear your cookies automatically upon exit [how-to link]

Chrome and Internet Explorer are also supporting this behavior, so this is fantastic news for everyone's privacy on the web!

More reading for techies:

13 comments:

Erunno said...

Chrome will integrate LSOs into its regular cookie management panel starting with version 12 (i.e. LSOs will appear alongside cookies and localstorage for each domain listed there). Are there similar plans for Firefox?

Jo Hermans said...

https://bugzilla.mozilla.org/show_bug.cgi?id=632789

Dan said...

Does this interact well with Private Browsing mode too?

Erunno said...

@Dan

Flash already respects private browsing since 10.1.

Anonymous said...

@Jo Hermans

632789 is a SeaMonkey bug.

James said...

LSOs contain saved data and settings for flash applications like games, correct? I wonder how many people will end up unintentionally erasing all their saved progress.

James said...

@Erunno

See the BetterPrivacy addon.

Erunno said...

@James

Yes, I know of BetterPrivacy as I've been using it for quite some time. That doesn't really answer my question though. Will Mozilla integrate LSOs (and any other persistent data from widespread plug-ins) it into its planned brand new privacy center?

Sid Stamm said...

@Erunno/10:23am:
I'm not sure what you refer to when you say "brand new privacy center"...

With respect to our existing cookie interface... I'd like to see deleting LSOs line up with cookies elsewhere in the Firefox UI too. For example, it would be nice if I could delete LSOs and cookies for individual sites. We don't have firm plans in this area yet, but we surely haven't ruled it out.

Erunno said...

@Sid

Tthere are/were plans to completely redesign the privacy panel.

http://jboriss.wordpress.com/2010/06/02/defeating-the-cookie-monster-how-firefox-can-improve-online-privacy/

Sid Stamm said...

@Erunno: yup, I'm pretty aware of that (https://wiki.mozilla.org/Privacy/Features/Site-based_data_management_UI). We'll have to make sure LSOs are addressed on that panel (though they may be lumped in with the "cookies" permission).

Erunno said...

@Sid

Doh! You are the owner of this feature. My bad. :)

Anonymous said...

See https://bugzilla.mozilla.org/show_bug.cgi?id=685136