I'm building an ecommerce store with Woocommerce for WordPress using the Storefront theme. I created a child theme to remove the default sidebar, however this also has the side effect that widgets in the footer widget areas are not displayed. If I switch back to the parent theme, they work just fine.

This is the functions.php of the child theme:

```
<?php
function mb_remove_sidebar() {
    return false;
}

add_filter( 'is_active_sidebar', 'mb_remove_sidebar', 10, 2 );

```

How can I get the footer widgets back?