Hiding variants from storefront works perfectly on single-option products, but breaks on multi-option ones

Short description of issue

Hiding variants from storefront works perfectly on single-option products, but breaks on multi-option ones

Link to Shopify Store

Reproduction steps

Create a product with two options (e.g. Size: Small/Medium × Color: Red/Blue)
In the Shopify Admin, go to the product’s variants and unpublish the Small/Blue variant

Reload the storefront product page with Small selected

Expected: Blue is hidden from the Color selector
Actual: Blue still appears but with a strikethrough as “unavailable”

Additional info

Note: If you unpublish all variants under Small (both Small/Red and Small/Blue), then Small disappears correctly. The bug only occurs when unpublishing a partial set of variants within a multi-option product.

What type of topic is this

Troubleshooting

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