Right after the Summer 21 update to our sandbox, we logged in and found that our B2B installation had broken; none of the B2B objects were available (ProductCategoryProduct, ProductMedia, etc.), the Administration page was throwing errors about not having access to WebStore and various 'Page Not Found Errors' were abound. What happened and how do we fix it?
Summer 21 introduces a new setting - Enable Commerce under Get Started with Commerce - and it appears to be disabled by default, regardless of whether or not you already had B2B LEX set up. To enable it, go to Setup -> Commerce -> Settings and toggle Enable Commerce.
Marco Solis reported this in the B2B Commerce Trailblazer group, and Venkat Medapati responded with this:
This was introduced to make B2B Lightning more broadly available with developer edition support with the summer release. Note that you would not need to update manually when the release rolls out to production in June as those will be updated automatically.
So while this might cause some issues in the short term, we shouldn't see this issue again when Summer 21 goes to production, and it sounds like we'll get a taste of B2B in the Developer Edition orgs.