The page at ’https://yourblog.com’ was loaded over HTTPS, but ran insecure content from ’http://yourblog.com/wp-content/plugins/bad-plugin/required-asset.js’
The issue here is that the plugin is not using the correct URL when specifying the required-asset.js (or whatever the file is in your case) file path.
The fix it pretty easy.
Upon looking into the plugin code I noticed that it was using the deprecated constant
Here is the deprecated code:
define ('PLAYERSS_URL', WP_PLUGIN_URL .'/'. plugin_basename(dirname(__FILE__)) );
Here is the updated code:
define ('PLAYERSS_URL', plugins_url( '/', __FILE__));