Issue Summary

When adding a "Single Select Dropdown" field to ProForma Forms with a few options, users are not allowed to deselect all options and set the field to NULL after selecting an option from the "Single Select" pick field. This should be aligned to the native Jira Single-select custom field, which allows a null option by default if the user wants to deselect the chosen option.

Steps to Reproduce

Step 1: Configure the Form

1. Navigate to your Jira Service Management project and select Project settings from the sidebar.

1. Choose Forms from the left-hand settings panel.

1. Select Create form (or edit an existing one).

1. Add a Dropdown (single choice) question to the form and enter a few sample choices.

1. In the form settings, ensure the form is linked to a specific Customer request type so it is visible and usable in the Customer Portal.

1. Save and publish your changes.

Step 2: Reproduce the Behaviour in the Portal

1. Open the Customer Portal and navigate to the request type where you just activated the form.

1. Locate the dropdown question you created and select a value from the list.

1. Attempt to clear or remove the chosen value to return the field to its original empty state.

1. Observation: You will notice that once a selection is made, there is no option to deselect it or leave the field blank again.

Expected Results

There should be a NULL option or equivalent if the user wants to clear out the choice selection.

Actual Results

No option to deselct.

Workaround

Add another option like ‘None / Not Applicable' but might not be feasible for all.
Currently there is no known workaround for this behavior. A workaround will be added here when available