Can you provide more details on what you want to do? Is it in the desktop application or in the web library, which operating system, which browser if relevant, can you give a screenshot of where you drop the PDF file, do you get any error after dropping? https://www.zotero.org/support/reporting_problems#provide_steps_to_reproduce
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Is it in the desktop application or in the web library, which operating system, which browser if relevant, can you give a screenshot of where you drop the PDF file, do you get any error after dropping?
https://www.zotero.org/support/reporting_problems#provide_steps_to_reproduce