Any idea of when cleanup will include DOM and user persistent data (local storage objects) under the Internet Explorer cleanup category? Below is my canned comment to users that don't understand that .txt cookies aren't the only means of saving data on their host from a server. LSO can be used to store information on the user's host and, for example, can also be used to track their web navigation. I have disabled both DOM Storage and UserData Persistence options in IE8 but this could interfere with the operation of some sites; for example, they may want to use local storage for data used by a script on their web page that I visit. When I am no longer at the site, and especially after exiting the web browser, I don't want this data stored on my host. My property is not to be used for their storage.
Also, under your Multimedia category, you list Adobe Flash Player but don't mention just what gets cleaned up. Maybe that means deleting the .sol cookie files used for local storage by Flash. However, if you delete the global .sol cookie file then the user loses all their settings for the ActiveX control for Flash (which can include settings to NOT let the control use any local storage to pollute their host). I currently have the Flash Player configured to NOT allow for local storage but if CCleaner deletes the global .sol cookie (%appdata%\Macromedia\Flash Player\macromedia.com\support\flashplayer\sys\settings.sol) then I lose my settings and am back to the defaults which does allow local storage.
- CCleaner should add cleanup for DOM Storage and persistent user data.
- CCleaner should not delete the global .sol cookie that hold the user's settings for Flash Player.
- docs.piriform.com should get updated to include a Tech Specs section to let users know exactly WHAT cleanup actions are perform by each setting under Windows and Applications tabs.
-- DOM Storage and UserData Persistence
Cookies only allow a small amount of storage on your host: typically 300 cookies total, 20 cookies per domain, 4096 bytes per cookie. These are the recommended minimums [but are *not* required] by RFC 2109. IE goes its own way with a maximum cookie count of 20 (but got upped to 50) with a total of 4096 bytes maximum consumed by all cookies (upped to 10KB in IE8); see http://blogs.msdn.com/ieinternals/archive/2009/08/20/WinINET-IE-Cookie-Internals-FAQ.aspx. You'll have to do your own research regarding maximums in other web browsers. Some web servers also have their own maximums. Apache will fail with "Size of a request header field exceeds server limit" if the total of all cookies retrieved by the Cookie: request header exceeds 8190 bytes.
For info on .txt cookies: http://en.wikipedia.org/wiki/Http_cookie
Another source of cookies are with Flash which has its own .sol files. You can manage how big they can become or if any are saved on your host at all. Visit http://www.macromedia.com/support/documentation/en/flashplayer/help/settings_manager.html and go under Global Settings to configure if any local storage is used.
For info on .sol cookies: http://en.wikipedia.org/wiki/Flash_cookie
Cookies are not the only means of saving site data (euphemistically called "user data" for a site) on your host. User persistent data is a separate cache and allows far more storage of site data on your host. Check if you have the following options enabled:
Internet Options
- Advanced tab
Security section
Enable DOM Storage
- Security tab
<pick a security zone, like Internet>
Custom Level
Miscellaneous section
Userdata persistence
See:
http://msdn.microsoft.com/en-us/library/cc197062(VS.85).aspx
http://en.wikipedia.org/wiki/DOM_storage
https://developer.mozilla.org/En/DOM:Storage#Description
DOM storage is new as of IE8 (http://dev.w3.org/html5/webstorage/). As I recall, the persistent data is stored under the %userprofile%\UserData folder for IE. Other web browsers have their own DOM storage location (e.g., Firefox uses an SQLlite file). I've had these options disabled for so long and probably did cleanup at the time that there is nothing to find on my host under this folder. There may be freeware that not only purges the classic .txt cookies (and possibly the Flash .sol cookies) but also the UserData records.