my entire library duplicated itself
dstillman
Zotero Team
This discussion was created from comments split from: Merging duplicate references bug in Zotero 9.0 (64-bit).
Upgrade Storage
A duplicate library would be due to using export/import on one computer in addition to syncing from another. Sort the items list by Date Added and you can likely see the entire set of items you imported. If you haven't used those anywhere (e.g., in a word processor document) or moved them into collections, you can just delete them. If you've done more, it's hard to give general advice.