Notices from earlier cache helper change
[2.2] Product attribute shortcode should return columns class

Fixes #6481
[2.2] Prevent address fields being empty when editing an address within an order

Fixes #6476
[2.2] Added woocommerce_product_subcategories_hide_empty filter

Use add_filter( ‘woocommerce_product_subcategories_hide_empty’,
‘__return_true’ ); to enable. Fixes #6482
[2.2] Prevent bulk edit from breaking sale price scheduled dates

Fixes #6474
2.2.6 Readme + version bump