Thank you. I was having difficulty with the "mixed content" warning for one of my forums which exists as a subdomain.
I tried a competitive add-on which sadly did not work for me.
Your instructions for installing this add-on are a little ambiguous
- files and folders to upload (cache-img and images folders, cache.html, cache.php) might be better packaged under the standard Upload folder
- you need to add the instruction to change the properties of the cache-img folder to 777 after uploading
- the instructions on replacing [LINK_TO_YOUR_WEBSITE] with the domain of the forum might explicitly state "including the square brackets"
but I am very happy to report that this completely resolved the mixed content issue for me. :up: