I’ve just tested this and I’m not seeing any issue with the weight field in WC.
What could cause this?
You have created a field with the name “weight” in ACF. The field name that is used by WC is “_weight”. ACF uses the meta key of “_weight” to store the ACF field key reference for this “weight” field. The random number you are seeing is probably the numeric portion of ACF’s field key for the field.
Rename the ACF field and avoid using field names that exist in plugins used on your site when attaching them to WP objects that use those fields.
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