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Currently migration for ‘Shared Modifier Options’ and ‘Shared Variant Options’ for products isnt supported in StagingPro (on the destination store Control Panel under Product > Product Options, under the 'Shared Options' and 'Shared modifiers' tabs will show as empty since the option datasets dont migrate). However, unlike Shared options, regular modifier options & regular variant options for products will migrate across as per current implementation.
BigCommerce’s engineering team are reportedly working on sharing an API for this, so there isn't a confirmed ETA yet.
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