Private browsing in Opera is not so private actually

I've always been using Opera's private browsing when didn't want any history and other stuff to be saved locally. Always until I decided to take a look at how private it really is.
After some private browsing I navigated to ~/.opera/temporary_downloads and noticed that Opera stores some necessary files there. There were:

• crossdomain.xml (which may reveal domain you browsed in many cases)
• various swf files (which may reveal sensitive information when decompiled)
• strange video_related.htm file, which contained a lot of info
  

That's fine, but the actual problem is that Opera doesn't delete the files when closed. It only do this when opened in next time. It works so regardless private or usual navigation. And I doubt anyone opens Opera again just to clear files after private browsing.
So, Opera's private browsing is not so private actually.

Drupal and cookies domain caching

From time to time anyone experience some problems with non-fresh Drupal installations (e.g. some project from SCM). The major one for me was some strange cookie setting and handling - when I tried to login Drupal replied with correct Set-Cookie header, but cookies were not saved within browser, i.e. after login the page was just reloaded with login prompt. No message or anything to help me. So I just started commenting and editing related code by random. Finally, I got it. The problem is that Drupal was installed first with hostname A and I tried to work with it on hostname B. Don't know why sometimes it's okay and sometimes it's not. However, you just need to uncomment $cookie_domain and set it to your hostname in settings.php. Just like this:

$cookie_domain = 'your.domain';