Bug: Adding PDF from the Finder in Zotero 5 (standalone) by drag&drop is not reliable.
Most of the time the PDF don't show up, but show up if I restart Zotero. Sometimes, it show up but the PDF is not in the library....
Btw the interface to drop a PDF in Zotero is not very intuitive. It's sometimes hard to drop it in the library without doping it in the first item of the library.
Is it possible you're just dragging to the wrong area? I'm not seeing any problems dragging PDFs in, and there's no particular reason this should act inconsistently. Note that when you drag a file in, you can either drop it over an item — which turns the row gray and makes the file a child attachment — or you can drag it in as a standalone attachment, which is what you get if you see a line between items.
If you think something's not working, can you figure out a specific way to reproduce the problem?
(The one thing I would call a bug is that you get the line even when you're dragging among an item's child items. In that case it would make more sense for Zotero to create a child attachment rather than a standalone attachment. But at the moment, to create a child item you just need to drag on top of the parent.)
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Most of the time the PDF don't show up, but show up if I restart Zotero. Sometimes, it show up but the PDF is not in the library....
Btw the interface to drop a PDF in Zotero is not very intuitive. It's sometimes hard to drop it in the library without doping it in the first item of the library.
If you think something's not working, can you figure out a specific way to reproduce the problem?
(The one thing I would call a bug is that you get the line even when you're dragging among an item's child items. In that case it would make more sense for Zotero to create a child attachment rather than a standalone attachment. But at the moment, to create a child item you just need to drag on top of the parent.)