In planning view, when I try to "unplan" a backlog item, there is an error message like "Conflict: item is not in unassigned backlog". By "unplan" I mean:
- Assuming you have a Submilestone (or a Top milestone) with a backlog item in it
- Move the backlog item from the milestone to the backlog (left part of planning view)
It has the same root cause as request #14860. Upgrading dragular somehow causes a duplicate drop event to happen, which brings the error message.
Issue has been introduced by git #tuleap/stable/f73754592f08d32cc167e8a6ee04e2869f22a8c8