* Fix - Fixed an issue where the subtotal price for a variable product was shown incorrectly on a product page.
* Fix - Fixes an issue in the admin panel when adding add ons.
* Tweak - WC 6.1 compatibility.
* Tweak - WP 5.8 compatibility.
* Fix - Escape output in some places across the plugin.
* Fix - Improve performance when displaying many global product addons.
* Tweak - WC 5.9 compatibility.
* Tweak - WP 5.8 compatibility.
