Current Behaviour - In the current set-up, it's easy for Kanban story and issue cards to easily fall-off/disappear from board (if they are changed to the wrong status or if someone accidently removes the team assignment). I'm hoping this can be updated with a more fool-proof method so that cards don't go missing.
Why is this feature important to you - It would allow users to have more confidence in the board and not worry about their story/issue cards disappearing and then needing to search to find them.
How would you like the feature to work - Some sort of indicator (other than just the assignment or card status) that would indicate it belongs on a Kanban board. Once it is on the board, it's not possible to remove unless completed, cancelled or deleted.