Upgradable and blockable mixed content

Given these blurry lines between active and passive mixed content, the latest revision of the Mixed content standard distinguishes between blockable and upgradable content, where scripts, iframes, responsive images and really all other features are considered blockable. The formerly-called passive content types ( , and elements) are now being upgraded by the browser to use HTTPS and are not loaded if they are unavailable via HTTPS. This also introduces a behavior change in our security indicators: Firefox will no longer make use of the tiny warning sign in the lower right corner of the lock icon: After our change. A fully secure lock icon. The image load was successfully upgraded or failed (e.

g. , Connection Reset). With Firefox 127, all mixed content will either be blocked or upgraded. Making sure that documents transferred with HTTPS remain fully secure and encrypted.