id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
12617	Unexpected deletion of members by drag-n-drop in relation editor	verdy_p	team	"I discovered the drag-n-drop was implemented first because it created a serious bug when editing complex relations (notably those containing hundreds of members).

It frequently happens that we slighly drag the mouse while clicking, and in some case this causes an immediate move of items in the list (which is refreshed and repositioned, so we don't see what happened and which members are affected).

But more dramatically, some moves, when we already have multiple elements selected in the list, will cause them to be REMOVED unpexpectedly from the list of members, causing a dramatic change.

Please add a confirmation dialog if a drag-n-drop operation causes any members to be removed from the list (not just moved elsewhere in the list), and notably if the operation if on a selection of multiple members!

For now the new drag-n-drop feature in the relation editors is extremely dangerous! We may not even see that some members were effectively removed from the list, and if we apply the changes we won't see that there are less members than before

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Note also that the pane showing the history of changes does not even indicate how many members were added or removed when applying changes and closing the relation editor.

We ONLY see that the relation was changed, without more details: we should have a ""+"" icon showing details, containing at least:

* the list of members added, and the list of members removed, and we should be able to select elements from these list, to help restoring elements that were unexpectedly removed from the list of members, without necessarily having to completely revert ALL edits made in the relation editor;
* it should also probably say if tags were modified, just like with other elements (nodes/ways) or when editing tags from the tags pane (outside the relation editor itself).
"	defect	closed	major	16.04	Core		fixed	relation member drag-and-drop	simon04