Category is not retained when a note is shared

The requirement we are trying to implement in our organization is for the technical support team to create self-help documentation in the form of notes and share them with other Nextcloud users within our organization. For this to work well, individual notes have to be categorized so users can find content easily. We rely on the category feature of notes where we can assign a category to a note. Example: we want to use categories like "email", "calendar","laptop" etc. Unfortunately, we observe that the categories we assign to notes are getting lost when shared with other users.

The issue is a blocker for us to use the notes app. We will have a few dozen notes to share with users and we will also encourage users to create their own notes and share. Without the ability to share categorized notes and view notes in category folders for the users, everyone will see a very long list of notes in a single 'uncategorized' folder view, and it will be difficult to find information.

A workaround to use tag based search is not very helpful as a list of notes tags are not available. The notes app search does not search for tags, so users have to use the full nextcloud search.

Steps to reproduce

1. Create a note. Add a category to the note, say 'tutorial'
2. Add some content.
3. Share with another user, say user X, with view-only permission (the actual share permission level does not matter, we have tried with edit permission also, same result as below)
4. Login to Nextcloud as user X, go to Notes app

Expected behaviour

User X should see the note shared with them. They should be able to see the category label 'tutorial' in the list of categories. On clicking the category 'tutorial', they should be able to see the note shared with them.

Actual behaviour

User X is able to see the note shared with them. But there is only one default category 'uncategorized' shown to them. The category 'tutorial' is missing. The category label shown for the note is the default 'uncategorized'. The original label 'tutorial' is lost.

Server

Please complete the following information.

• Notes app version: 4.10.1
• Nextcloud version: 28.0.6
• OS: Linux
• Web server: Don't know. Managed hosting by Hetzner
• PHP version: Don't know. Managed hosting by Hetzner
• Database: Don't know. Managed hosting by Hetzner

Client

Please complete the following information.

• Browser (incl. version): Firefox 128, but issue is browser independent. Same behavior on Chrome also
• OS: Ubuntu Linux

Start by reproducing the issue using the listed steps with a categorized note shared to another user, then inspect the note-sharing and category-loading paths. Done means the recipient sees the original category and can find the shared note through that category, with coverage for the reported permissions.