Custom content operations not shown for spaces

I have a custom content type whose supported container type is “space”. Yet when I expand the operations field on a space it does not contain the create operation for that type, even though I have the required permissions. Supported space permissions (supportedSpacePermissions field in the app descriptor) for the custom content type are “create”, “read”, and “delete”.

Response from /rest/api/space/{spaceKey}?expand=operations:

{
    …
    "operations": [
        {
            "operation": "read",
            "targetType": "space"
        },
        {
            "operation": "update",
            "targetType": "space"
        },
        {
            "operation": "delete",
            "targetType": "space"
        },
        {
            "operation": "export",
            "targetType": "space"
        },
        {
            "operation": "administer",
            "targetType": "space"
        },
        {
            "operation": "create",
            "targetType": "page"
        },
        {
            "operation": "create",
            "targetType": "blogpost"
        },
        {
            "operation": "create",
            "targetType": "comment"
        },
        {
            "operation": "create",
            "targetType": "attachment"
        }
    ],
    …
}

The operation fields of pages do show operations for custom content (if that custom content type has “page” as a supported container type). It seems to also work for other content types, even custom content.

Response from /rest/api/content/{contentId}?expand=operations:

{
    …
    "operations": [
        {
            "operation": "read",
            "targetType": "page"
        },
        {
            "operation": "update",
            "targetType": "page"
        },
        {
            "operation": "delete",
            "targetType": "page"
        },
        {
            "operation": "restrict_content",
            "targetType": "page"
        },
        {
            "operation": "clear_permissions",
            "targetType": "page"
        },
        {
            "operation": "archive",
            "targetType": "page"
        },
        {
            "operation": "create",
            "targetType": "ac:my-app:my-content"
        },
        {
            "operation": "create",
            "targetType": "attachment"
        },
        {
            "operation": "create",
            "targetType": "comment"
        },
        {
            "operation": "create",
            "targetType": "page"
        }
    ],
    …
}

Is there a workaround?
Can we please get a fix for this?