Optional Custom Column on Custom List Not Showing Up On Form (Does if Required)

Question

This seems like a Sharepoint bug... I created a custom list based on a custom content type. Those fields all show up correctly.

Additionally, I added a custom lookup field to the custom list, to look up to another custom list (which also uses a custom content type - likely irrelevant, but you never know).

IF I do not specify "Allow Blank Values":

Then the fields show up on the "New Item" form:

However, if I uncheck "Allow blank values?":

Then the fields do NOT show up on the new item form!

I EXPECTED this:

Answer 1

Your new field needs to be a part of the content type to be displayed on the new/edit forms.

I think the easiest solution is to go to list settings (on UI), find the content type (Category Factory Implementation Plan List Item), click on it to open its customization page. Click on "Add from list columns" link on the page, and add the "Opportunities" column there. Once you do this, you will get the form correctly showing the new column.

A better way to do this might to create a new site column, then add it to the site content type and then update the list content type, by adding the site column.

However I am not sure how to do this on SP Designer.