Seems like there has been some massive deletion of trails around here:
How can we find the culprit? Can we revert?

Looks suspicious, as too many deleted nodes. Asked user in his changeset discussion.
Can you figure what exactly changed?

I couldn’t figure out who deleted all this. Can you?

Sorry for coming from nowhere :wink:
Use Achavi for a meaningful changeset overview.
Apparently the user did shift the shapes, but oddly nodes got deleted and not moved.

Constructive help is always welcome!
How did you discovered this great tool?

I have no idea, most probably screwing around on the Wiki learning about Overpass attic data :wink:
I recommend you also do, as this enables very nice edit visualization and viewing snapshots at some point in history.
Moreover there’s a bookmarklet for Achavi you can place in your favorites to lanuch it from a changeset page.