Tag for Chrome & FF23+ all the rulesets where mixed content breaks things (!)
Recent versions of Chromium and Chrome have implemented an automatic mechanism to block the loading of insecure HTTP scripts from HTTPS origins. At first there was a loud popup message whenever that happened, but now the only indication in the UI is a small shield in the address bar, which the user can click on to force the insecure scripts to load.
Google has replied "won't fix" to any UX or extension API requests we made about this: https://code.google.com/p/chromium/issues/detail?id=144637
As a result, we are going to need a major push to identify rulesets that break sites in Chrome because of this mechanism, and disable them on that platform. This ticket will track that task.