Really Simple SSL inserts a marker “data-rsssl” in the websource as a way to check if it’s working. If it it’s there the mixed content fixer is active.
Really Simple SSL requests your homepage, and parses the websource for this marker to be able to put on the configuration page a notification if the mixed content fixer is active. If the marker is not found, you get an error there. But you also get an error when your homepage could not be loaded, like when you’re behind an under construction page. In that case you might see:
The mixed content is activated, but could not be detected on the front-end
This notice does not necessarily mean the mixed content fixer doesn’t work, it just means the page couldn’t be loaded to check that. Follow these steps to check what the problem is:
- Check manually if the mixed content fixer is active. If you encounter the comment, you can ignore this notice, as it apparently works. This sometimes happens when a server or security plugin blocks the plugin from opening a page on the website. How to test:
- Right click on your website
- click “view source”
- Look for the mixed content fixer marker: data-rsssl=1
- If it’s there, the mixed content fixer is active, and you’re done.
- If you have a caching plugin activated, the cache might still contain the websource without the marker. You can easily solve this by clearing your cache, then reload your configuration page. Really Simple SSL already clears the cache for some plugins, but not all of them.
- Check if you do have mixed content on your site. (Green lock in browser address bar) If you don’t have mixed content, you’re good!
- Another plugin conflicts with the working of the mixed content fixer. In this case you can change the hook the mixed content fixer fires on by adding
define( 'RSSSL_CONTENT_FIXER_ON_INIT', 'true' );
to your wp-config.php. That should resolve the issue in most cases.