Not sure if this is the right place for this, but as a slight change, I would suggest:
When clicking 'Import Annotations', it is not fully clear that the Annotations are **deleted** from the original PDF. (I realize it says "moved" and not "copied", but presumably most users don't understand the implications of a "move" operation.) Therefore, in the confirmation dialog that opens with 'Import Annotations,' I would suggest adding some text to clarify that the annotations will be removed from the PDF file itself when they are moved into Zotero.
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When clicking 'Import Annotations', it is not fully clear that the Annotations are **deleted** from the original PDF. (I realize it says "moved" and not "copied", but presumably most users don't understand the implications of a "move" operation.) Therefore, in the confirmation dialog that opens with 'Import Annotations,' I would suggest adding some text to clarify that the annotations will be removed from the PDF file itself when they are moved into Zotero.