Thread messages are lost/hidden when resuming a session #38006

What issue are you seeing?

Messages from existing threads are not preserved when a session is resumed.

After resuming a previous session, the threads are restored, but their message history is missing or incomplete.

What steps can reproduce the bug?

1. Start a new thread
2. Close it
3. Resume the thread

What is the expected behavior?

All thread messages should be preserved and restored when resuming a session.

Additional information

The session resumes without retaining the full message history of its threads.