Include drop-down choices in Content Definitions API

When setting up a Drop-down list property on a ContentType, the drop-down choices aren't included in the content definition when queried via the Content Definitions API.

In the attached screenshot you can see that I've defined 3 options for my drop-down list and when I use the /api/episerver/v3.0/contentmanifest endpoint, my content type does not include these choices.

Here is a snippet from the content manifest generated by the content type in my attached screenshot:

"properties": [
{
"name": "DropdownOptions",

"dataType": "PropertyDropDownList",

"branchSpecific": false,

"editSettings": {

"visibility": "default",

"displayName": "DropdownOptions",

"groupName": "Categories",

"sortOrder": 0,

"helpText": ""

}

}
]