Error Customizer Boutique Storefront

I’m getting an blinking error message on top of the page in the customizer from STorefront with child theme Boutique. saying:

Warning: Creating default object from empty value in /var/www/vhosts/mydomain.nl/httpdocs/Wordpress2016/wp-content/themes/storefront/inc/customizer/class-storefront-customizer.php on line 105

Its a new install for a fresh website. Did not change a lot only installed plugins like Woocommerce.
Anyone has an idea?
Thanks in advance.