If you get error like this:
SecurityError: Error #2122: Security sandbox violation: LoaderInfo.content: http://mydomain.com/my.swf cannot access https://fbcdn-profile-a.akamaihd.net/hprofile-ak-snc4/1234_1424341323_7322_s.jpg. A policy file is required, but the checkPolicyFile flag was not set when this media was loaded.
You need to load policy file from facebook by
Security.loadPolicyFile("https://fbcdn-profile-a.akamaihd.net/crossdomain.xml");
Before today it was enough to load it from here
Security.loadPolicyFile("http://profile.ak.fbcdn.net/crossdomain.xml");
Waiting for news from Facebook or Adobe about these changes.