I am having a new problem with WordPress 3.5 that I did not have with 3.4.2. I do all my site administration over SSL (my wp-config file has the following line:
define('FORCE_SSL_ADMIN', true);). When I go to the dashboard I see the green padlock in the address bar, so I know my SSL certificate is working properly. With WP 3.5., when I go to my media library, instead of the green padlock I get a message saying that while my connection is encrypted, the page "includes other resources that are not secure" and that can be viewed by others while in transit or modified by an attacker. Yikes! If I click once on the button to take me back to the dashboard, I can navigate back to the dashboard, but the warning remains. But if I click on the dashboard button again, the green padlock returns.
In case it is useful, I use the following theme: WooThemes Canvas v. 5.0.13, and the following plugins:
Broken Link Checker
NextScripts: Social Networks Auto-Poster
Prevent Password Resetn
Quick Page/Post Redirect Plugin