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In the S4S Mapping Wizard, map the hidden field in the same way that you would map any of the other fields:.
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2. Use custom css class to turn any existing form field into hidden form field.
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Then add the CSS class to whichever form field you want hidden on the form.
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The form field is visible in the Forms Designer, and within the Mapping Wizard.
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Publish relevant Sitecore items.Publish relevant Sitecore items.
In the S4S Mapping Wizard, map the hidden field in the same way that you would map any of the other fields.
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