When you change type of a citation, and this leads to loss of information, it would be really good if the lost information could be captured in a note.
One possible implementation would be to be able to place the 'exported RIS' for the item into a new item note. This is of course possible manually, but it's a bit cumbersome. Of course this proposal isn't very elegant, as it simply preserves all information, but at least it means information can be retrieved (assuming all item, information is output to the RIS).
Just to add to this: It would be great if the deleted item ID would also be preserved. This is helpful for scannable cites. ( @adamsmith ; also for copying the link via Zutilo, @bwiernik )
I understand why you'd find this useful, but overall my sense is that users are not pleased about getting notes generated automatically. I don't think we should do this.
When you merge items, Zotero creates a relation for the merged item that is “sameAs: DeletedID”. This gets picked up when the Deleted ID is referenced in the word processor plugin or ODF Scan.
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@bwiernik - so how does scannable scite locate an item where the item ID has changed? Are previous item ids recorded somehow?
For example, if I merge two items, zotero no longer finds the removed item ID via search.