I recently learned about a browser feature where, if you provide a special HTTP header, it will automatically post to a URL with a report of any non-HTTPS content. This would be a great thing to do when transitioning a site to HTTPS, for example, to root out any mixed content warnings. In this article, we’ll implement this feature via a small WordPress plugin.
What is mixed content?
“Mixed content" means you’re loading a page over HTTPS page, but some …
Content Security Policy: The Easy Way to Prevent Mixed Content is a post from CSS-Tricks