Steps to reproduce the behavior:
I have installed vanilla Woocommerce with Storefront theme and this plugin with wp-graphql.
When I click add to cart the product is added to the cart and page refreshed with correct items in cart. However on page load there is an ajax call /?wc-ajax=get_refreshed_fragments. Response from that cart clears cart_hash cookie and returns 0 products in cart.
This does not happen when plugin is deactivated.
Screenshots

The is most likely due to the QL_Session_Handler. Sounds like it's preventing the woocommerce session cookie from being updated property. This is definitely a bug, since the QL_Session_Handler shouldn't be used on non-GraphQL request. I'm not too familiar with the wc-ajax action, I'll have to look into it. :thinking:
Fixed in #146. @pristas-peter thanks for catching this one. It would have been a pain down the line.
Most helpful comment
The is most likely due to the QL_Session_Handler. Sounds like it's preventing the woocommerce session cookie from being updated property. This is definitely a bug, since the QL_Session_Handler shouldn't be used on non-GraphQL request. I'm not too familiar with the
wc-ajaxaction, I'll have to look into it. :thinking: