Hi @SongbaiZHANG, if possible, could you make a quick video (screen recording) of what's going on? In logs I can only see you cancelled the download.
Can you please try to: 1. Start screen recording 2. Start debug logging 3. Try to download some PDF 4. When it fails stop debug logging and stop screen recording 5. Post debug id and video here or send it to support@zotero.org
Can you please try to:
1. Start screen recording
2. Start debug logging
3. Try to download some PDF
4. When it fails stop debug logging and stop screen recording
5. Post debug id and video here or send it to support@zotero.org
Thanks!