A new setting lets you control whether upsell recommendations preselect a variant that matches what's already in the customer's cart — for example, automatically preselecting size 12 on a recommendation when the customer already has a size 12 in their cart.
What's new. When you open an upsell component's "Appearance and settings" panel, you'll see a new "Match cart variants" checkbox under Settings. It's turned on by default for both new and existing upsells.
What it does. With the setting on, recommendations preselect a variant whose options — size, colour, or any other variant option — overlap what's already in the customer's cart. The customer can still pick a different variant if they want.
When to turn it off. Some merchants prefer their upsells to always show the first available variant, regardless of what's in the cart. For example, you might be running a "Featured colour" promotion where you always want the featured variant shown first. Turning off "Match cart variants" gives you that behaviour. It also stops the upsell from hiding single-variant products that don't match the cart's selections.
Existing components unchanged. Every upsell already in production continues to behave exactly as before — the matching only stops if you explicitly turn the new setting off.