Property expansion and limiting isn't working properly

[cvagan]

Which Umbraco version are you using?

17.0.0

Bug summary

The output from the Delivery API seems to be the same regardless of whether the values for expand and fields are included in the query.

Specifics

Endpoint: /umbraco/delivery/api/v2/content/item/{id}

Default output without any query strings:

{
  "contentType": "base",
  "name": "Child page",
  "createDate": "2025-11-27T13:10:14.717Z",
  "updateDate": "2025-11-27T13:52:09.157Z",
  "route": {
    "path": "/child-page/",
    "queryString": null,
    "startItem": {
      "id": "09ff2846-ac93-4e97-bc51-51ff1f6bc0b6",
      "path": "root"
    }
  },
  "id": "fecad7b7-31dc-49a7-904a-e8c733993a4c",
  "properties": {
    "pageTitle": "Child page title",
    "pageDescription": "Child page description",
    "contentList": null,
    "document": {
      "contentType": "base",
      "name": "Another page",
      "createDate": "2025-11-27T13:14:37.99Z",
      "updateDate": "2025-11-27T13:46:47.07Z",
      "route": {
        "path": "/child-page-2/another-page/",
        "queryString": null,
        "startItem": {
          "id": "09ff2846-ac93-4e97-bc51-51ff1f6bc0b6",
          "path": "root"
        }
      },
      "id": "42132b97-39eb-49bb-a1a8-9ccbe28a945e",
      "properties": {
        "pageTitle": "Another page's title",
        "pageDescription": "Another page's description",
        "contentList": null,
        "document": null,
        "image": [
          {
            "focalPoint": null,
            "crops": [],
            "id": "434882b9-5fba-4a67-8666-0c2e7dd14b94",
            "name": "986891.jpg",
            "mediaType": "Image",
            "url": "/media/gzea33ot/986891.jpg",
            "extension": "jpg",
            "width": 640,
            "height": 360,
            "bytes": 63853,
            "properties": {}
          }
        ]
      }
    },
    "image": null
  },
  "cultures": {}
}

Steps to reproduce

With the document type mentioned above, attempt these queries:

Attempt at getting only the pageTitle field with request URL https://localhost:5001/umbraco/delivery/api/v2/content/item/fecad7b7-31dc-49a7-904a-e8c733993a4c?fields=properties[pageTitle]

Attempt at expanding a nested altText property of a picture on the document property with request URL https://localhost:5001/umbraco/delivery/api/v2/content/item/fecad7b7-31dc-49a7-904a-e8c733993a4c?expand=properties[document[properties[image]]]&fields=properties[$all]

Making a request with an improperly formatted query value also does not produce any different result (e.g. adding too many or too few brackets in expand or fields). This used to produce a 500 response in 16.x versions of Umbraco.

Expected result / actual result

Expected results with limited fields and expanded properties, but all queries yield the same default result as above.

[github-actions]

Hi there @cvagan!

Firstly, a big thank you for raising this issue. Every piece of feedback we receive helps us to make Umbraco better.

We really appreciate your patience while we wait for our team to have a look at this but we wanted to let you know that we see this and share with you the plan for what comes next.

• We'll assess whether this issue relates to something that has already been fixed in a later version of the release that it has been raised for.
• If it's a bug, is it related to a release that we are actively supporting or is it related to a release that's in the end-of-life or security-only phase?
• We'll replicate the issue to ensure that the problem is as described.
• We'll decide whether the behavior is an issue or if the behavior is intended.

We wish we could work with everyone directly and assess your issue immediately but we're in the fortunate position of having lots of contributions to work with and only a few humans who are able to do it. We are making progress though and in the meantime, we will keep you in the loop and let you know when we have any questions.

Thanks, from your friendly Umbraco GitHub bot 🤖 🙂

[iOvergaard]

Hi @cvagan, thanks for the report. We are looking into it to verify.

[kjac]

I can reproduce this. By the looks of it, this is caused by the introduction of the ElementOnlyOutputExpansionStrategy in #20559

We'll look at a fix for this as soon as possible.

[kjac]

Please note that #20559 was backported to V13 in #20721, so V13 might also be affected.