Depricated lines

Hello, I’m seeing this warning on a WP installation:

Deprecated: Creation of dynamic property PowerpackElements\Classes\PP_Elements_WPML::$type is deprecated in /nas/xxxxxxxxxx/wp-content/plugins/powerpack-elements/classes/class-pp-wpml.php on line 7

Deprecated: Creation of dynamic property PP_SL_Plugin_Updater::$plugin_file is deprecated in /nas/xxxxxxxxxxx/wp-content/plugins/powerpack-elements/includes/updater/class-pp-plugin-updater.php on line 45

Deprecated: Creation of dynamic property PP_SL_Plugin_Updater::$failed_request_cache_key is deprecated in /nas/xxxxxxxxxx/wp-content/plugins/powerpack-elements/includes/updater/class-pp-plugin-updater.php on line 51