This documentation is not using the current rendering mechanism and will be deleted by December 31st, 2020. The extension maintainer should switch to the new system. Details on how to use the rendering mechanism can be found here.
This is the initial release of cart_products for TYPO3 v9. It is part of the cart extension.
If upgrading from cart version 4.8.1 or earlier: Please read the documentation very carefully! Please make a backup of your filesystem and database! If possible test the update in a test copy of your TYPO3 instance.