I've been a little hesitant to upgrade to Firefox 2.0 on my Mac since the option to block third party cookies was removed from the preferences pane. For those that don't know, third party cookies are cookies that come from sites you connect to other than the site you're browsing. For example, if you're browsing, say, Slashdot.org and advertisers on there send you cookies, that would be third party cookies. One of the biggest advertisers out there, DoubleClick, uses third party cookies to track your behavior. How you ask? Well, say you go from Slashdot (and they've already sent you a cookie) to another site like CNN. Now DoubleClick knows you've gone to both sites. What's worse is if individual pages within the site send you cookies. Now DoubleClick knows what you're reading. Knowing that, I'd say it's a good idea to block third party cookies.
Here's how it's done in Firefox 2. Open a new window or tab, then type 'about:config' in the address bar (without the quotes). In the filter bar, type 'network.cookie.cookieBehavior' (again, without the quotes). You should start seeing filter results as you type, but this is the name of the string you want to change. You've got three numeric options you can change it to:
0: All cookies are allowed. (Default)
1: Only cookies from the originating server are allowed.
2: No cookies are allowed.
3: Cookies are allowed based on the cookie P3P policy (Mozilla Suite only).
Obviously, option zero is the worst since allowing all cookies would allow third party cookies. Shame on the Mozilla team for making it the default! Option two would be nice, but it'd break many sites. Option three would work as long as you're using the full Mozilla suite (they still release it?). So option one is the one we want since it only allows cookies from the original (that is, first party) server. Double click the 'network.cookie.cookieBehavior' string and change the numeric value to 1. Click ok, then exit and re-open Firefox for the change to take effect. There, all better now!
W00-h00! Finally passed the last test. I took it a few months ago and failed pretty badly. This time around I continually reviewed my material to make sure I knew it cold. I'm glad I'm through with this certification. I may move towards the design track. But first, a much needed break.