What exactly do you by "I lost the files in my intended folder"? The items didn't end up in the collection you were dragging to, or you can't find them in Zotero anymore?
Even if something failed while moving items, that would never cause items to be lost from Zotero itself. Nothing has been deleted recently in your synced library.
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Even if something failed while moving items, that would never cause items to be lost from Zotero itself. Nothing has been deleted recently in your synced library.