Occasionally, I get an error when trying to add a subtask to a task I am currently working and get the message "Could not find parent project for this issue"
It does not happen every time and sometimes it will happen after I just added a subtask and am trying to add another.
I initially saw this happen when working on a task created via API, then again on a task created by another user. Now it has happened to a task I created myself. It happens in different projects, not always the same.