If you're getting "This page is trying to load scripts from unauthenticated sources" error, it's because Mustang is trying to protect you from a site that's not secure to make sure your information on the page doesn't fall into the wrong hands. If this happens, in the address bar you'll see a shield .
Usually, you can reload the page to fix the error. In the top left, click Reload.
Although not recommended, you can choose to override the alert for the page by clicking Load unsafe script. Mustang will refresh the page and load its content, including any insecure content. To show that the page isn't fully secure, the address bar at the top will show https crossed-out in red: .