Hello,
I've created ‘pll-config.php’ file in ‘/wp-content/polylang/’. The problem is in line 48 of polylang.php:
if (!defined('PLL_LOCAL_DIR'))
define('PLL_LOCAL_DIR', WP_CONTENT_DIR . '/polylang');
It should be:
define('PLL_LOCAL_DIR', WP_CONTENT_DIR . '/plugins/polylang');
because WP_CONTENT_DIR is '/srv/public-wordpress/wp-content'.
Best regards