If you notice that some of Divi Booster's settings are not being applied to your site, one possibility is that Divi Booster's CSS and JavaScript files aren't accessible from the browser. The files in question are located in your WordPress directory, at:

/wp-content/uploads/wtfdivi/wp_head.css
/wp-content/uploads/wtfdivi/wp_footer.js

When attempting to load these files, the browser may be receiving a 403 Forbidden error from your site. If you're having this issue and you browse to the files directly (add your domain to the start) you should see the 403 error in your browser. Alternatively, if you view your browser's JavaScript console on any front-end page you would see the 403 error message there. This means that something in your server configuration is blocking access to these files.

A common cause is security plugins which have been configured to prevent access to files within the WordPress uploads folder. If you have any security plugins running, please review their settings to ensure that access to the uploads folder is permitted. A quick way to test whether a particular plugin is blocking access is to temporarily disable it and refresh the page.

If the files don't appear to be blocked by a security plugin, I suggest contacting your web host to ask them to whether they are able to identify the server configuration issue which is preventing access to the files.

A workaround for the issue is to enable the "Developer Tools > Generated JS > Use inline JavaScript" option on the Divi Booster settings page. This will use an alternative method of adding the JavaScript which does not require the use of the wp_footer.js file, and allow Divi Booster to function correctly even if the 403 Forbidden error isn't resolved.

If you have, or suspect you're having this issue, and aren't able to solve it with the above steps, please contact me or leave a comment below.