Doesn't work with imaves. When I load a page over HTTPS that has images in it with insecure http:// urls, I expect these src attributes to be converted in DOM, so that the browser will no longer display the yellow exclamation mark warning me about mixed content. I can see even in the console that these images STILL load through HTTP. They only load through HTTPS when I do right click -> show image.
Additionally, the preferences page is mostly useless. It _hints_ that there is more functionality (some kind of "rules"), but there is no way to edit those, or the way to do so is undiscoverable.