Wrapped Create activity and its actor have different origins

[silverpill]

Describe the bug

Activity:

{
  "@context": "https://www.w3.org/ns/activitystreams",
  "actor": "https://gehirneimer.de/m/mbinReleases",
  "cc": [
    "https://gehirneimer.de/m/mbinReleases",
    "https://kbin.earth/u/haverholm/followers"
  ],
  "id": "https://gehirneimer.de/f/object/e2c7ebcb-8a92-4722-8546-582065809d48",
  "object": {
    "actor": "https://kbin.earth/u/haverholm",
    "cc": [
      "https://gehirneimer.de/m/mbinReleases",
      "https://kbin.earth/u/haverholm/followers"
    ],
    "id": "https://gehirneimer.de/f/object/1f1aa307-0138-4ffa-91b1-770a0ca09c5d",
    "object": {
      "attributedTo": "https://kbin.earth/u/haverholm",
      "cc": [
        "https://gehirneimer.de/m/mbinReleases",
        "https://kbin.earth/u/haverholm/followers"
      ],
      "content": "<blockquote>\n<p>Blocked or Deleted Users cannot send you private messages anymore</p>\n</blockquote>\n<p>Thanks devs! Sorry Nicole!</p>\n",
      "contentMap": {
        "en": "<blockquote>\n<p>Blocked or Deleted Users cannot send you private messages anymore</p>\n</blockquote>\n<p>Thanks devs! Sorry Nicole!</p>\n"
      },
      "id": "https://kbin.earth/m/[email protected]/t/1128375/-/comment/5895067",
      "inReplyTo": "https://gehirneimer.de/m/mbinReleases/t/557759",
      "mediaType": "text/html",
      "published": "2025-03-31T16:04:15+00:00",
      "sensitive": false,
      "source": {
        "content": ">Blocked or Deleted Users cannot send you private messages anymore\r\n\r\nThanks devs! Sorry Nicole!",
        "mediaType": "text/markdown"
      },
      "tag": [
        {
          "href": "https://gehirneimer.de/tag/mbinReleases",
          "name": "#mbinReleases",
          "type": "Hashtag"
        },
        {
          "href": "https://gehirneimer.de/u/BentiGorlich",
          "name": "@[email protected]",
          "type": "Mention"
        }
      ],
      "to": [
        "https://www.w3.org/ns/activitystreams#Public",
        "https://gehirneimer.de/u/BentiGorlich"
      ],
      "type": "Note",
      "url": "https://kbin.earth/m/[email protected]/t/1128375/-/comment/5895067"
    },
    "published": "2025-03-31T16:04:15+00:00",
    "to": [
      "https://www.w3.org/ns/activitystreams#Public",
      "https://gehirneimer.de/u/BentiGorlich"
    ],
    "type": "Create"
  },
  "published": "2025-03-31T16:04:17+00:00",
  "to": [
    "https://www.w3.org/ns/activitystreams#Public",
    "https://kbin.earth/u/haverholm"
  ],
  "type": "Announce"
}

Announce.object.actor is https://kbin.earth/u/haverholm
Announce.object.id is https://gehirneimer.de/f/object/1f1aa307-0138-4ffa-91b1-770a0ca09c5d

An actor from kbin.earth created activity on gehirneimer.de, but normally it shouldn't be allowed to do that. The created object doesn't have this problem, its id and attributedTo have same origin.

On which Mbin instance did you find the bug?

https://gehirneimer.de/

Which Mbin version was running on the instance?

1.8.1

Expected behavior

Announce.object.id and Announce.object.actor to be on the same domain.

[BentiGorlich]

You are absolutely right. I cannot tell you why it was initially implemented this way. I have been working for a fix for this (and a few other things) in #1173
So this issue will be solved by that PR