I can only select products on one page of the table at a time
WooCommerce Product Table has a 'Select All' link which appears in the table header when the add to cart checkboxes are enabled. This allows customers to select all the products in the table.
If you are not using the lazy load option then customers can select products across multiple pages of the table - either by clicking the ehckboxes or using the 'Select all' link - and add them to the cart all at once.
Unfortunately this is not possible when lazy load is enabled because by definition, it has only loaded the products in the current page of the table. As a result, if you are using lazy load then customers can only select products on the current page and must add them to their cart before moving to subsequent pages.
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