lib/W3/AdminActions/CdnActionsAdmin.php:371
$config = W3_Request::get_string('config');
$config = json_decode($config, true);
w3tc tries to read config as a string, but config is not a JSON encoded array but a PHP array
it gets "Array" as a value
Solution??
$config = W3_Request::get_array('config');
// $config = json_decode($config, true);
Works for me.
It would be good to have a github repo to have a Pull Request.