Unfortunately, it is not practically possible to disable all cookies. Cookies also serve to identify you to various servers, such as those requiring a login. Without accepting cookies, you will find using such services very difficult. Additionally, new features in web browsers mimic the behavior of cookies without the public being aware of it, nor how to counteract these “stealth cookies.”
Adobe Flash has implemented “Local Stored Objects” (or “flash cookies” if you prefer) as a feature of its browser plugin, while Mozilla has added something called “DOM Storage” in the most recent versions of Firefox. Either of these can be used by websites to track visitors without their knowledge.
If you use Firefox, it might be in your interest to turn off DOM storage. Open a browser window, type “about:config” into the address bar, and use the search field to look for “storage.” There should be a field called dom.storage.enabled, so set this to “false.”
To get rid of Flash cookies, we can start by seeing what Adobe recommends at
One glaring lack is that there is no “session only” configuration option. Instead, it is probably best to set Local Stored Object space to 0 for all websites, and only alter this for pages that you are willing to track you. In the Linux edition of the Flash plugin, I could not find a way to do this for all websites; so be aware of the risk. As mentioned above, Tails does not use Flash, which amongst other things precludes using YouTube. Therefore, if it is truly necessary to watch some video from online, download it using the appropriate browser plugin, store it on your hard drive and watch it from there. That should take care of any Flash cookies.