Sharing a file to a room results in increased unread marker

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Steps to reproduce

1. Upload a picture/file

Expected behaviour

Since I am sharing that file, the unread marker should not increase for myself.

Actual behaviour

The unread marker increases. This happens as soon as I share a file to a conversation:

curl 'https://sermo.nextcloud.com/ocs/v2.php/apps/files_sharing/api/v1/shares' \
  -H 'authority: sermo.nextcloud.com' \
  -H 'accept: application/json, text/plain, */*' \
  -H 'content-type: application/json' \
  -H 'cookie: <cookie>' \
  -H 'origin: https://sermo.nextcloud.com' \
  -H 'requesttoken: <token>' \
  --data-raw '{"shareType":10,"path":"//Talk/Bildschirmaufnahme 2023-05-06 um 14.25.51.mov","shareWith":"1234","referenceId":"asdf","talkMetaData":"{\"messageType\":\"\"}"}' \
  --compressed

(just copied from the browser). Each time this is executed, the file gets shared to the conversation and increases the unread marker. This can also be reproduced from talk-ios when sharing a file from outside of the app (go to photo library and then share with Nextcloud Talk, after opening the app you have unread messages).
Not 100% sure, but this wasn't the case in older versions, was it?

Note: This also happens when creating a Poll for example and directly leaving the conversation after creating it. When the sidebar refreshes, I have now 1 unread message in that conversation, which is my poll.

Talk app

sermo, master. Also seen on latest 26.

Start by reproducing the unread marker change with the file-sharing curl request or the Talk iOS sharing flow, then trace the conversation refresh after a shared file or poll is created. Done means the sender's own shared file or poll no longer increases that conversation's unread marker.