What

On the product edit page (Nutrition tab), under "Nutrition facts are specified for the product as sold," the "for 100 g" checkbox can be unchecked and the form saved successfully. When the product is opened for edit again, "for 100 g" is ticked again — the unchecked state is not persisted. The frontend does not indicate that this change was not saved (no validation, no error, no reflection of actual persisted state after save).

Steps to reproduce the behavior:

1. Go to a product edit page (e.g. world.openfoodfacts.org, product with nutrition data).
2. Open the Nutrition tab.
3. Under "Nutrition facts are specified for the product as sold," uncheck "for 100 g" so only "for 100 ml" is checked.
4. Save the product.
5. Re-open the same product for edit and go to the Nutrition tab.
6. See that "for 100 g" is ticked again (state was not persisted).

Expected behavior

Either the unchecked state is persisted and remains unchecked when re-opening, or the UI prevents saving that state and clearly informs the user (e.g. validation error or disabled option with explanation), so the user is not led to believe the change was saved.

Screenshots

Platform (Desktop, Mobile, Hunger Games)

• OS: Ubuntu
• Platform: Desktop (world.openfoodfacts.org in browser)