Custom Record Online Form > Select Fields > No option to select Section

When creating Online Form for a Custom Record, under Select Fields, there is no option for Section to choose.

Steps to reproduce:

1. Navigate to Customization > Lists, Records, & Fields > Record Types.
2. Edit the Custom Record.
3. Go to Online Forms > click on New Online Form.
4. Enter Title.
5. Under Select Fields, enter a Field.
6. Go to Section column.

Actual Results:

No option to select to assign Section for the field.

To resolve the problem, create a Subtab first for the Custom Record.

Steps to Reproduce:

1. Navigate to Customization > Lists, Records, & Fields > Record Types.
2. Edit the Custom Record.
3. Under Subtabs, enter a Title.
4. Click Save.
5. In the Online Forms tab > click on New Online Form.
6. Enter Title.
7. Under Select Fields, enter a Field.
8. In the Section column notice the Subtab will now appear under Section