The best way to start a File-Drag for now, is the downloadURL as i know.

Like here in Nylas N1:
https://github.com/nylas/N1/blob/master/internal_packages/attachments/lib/attachment-component.cjsx#L67

But only Images and PDFs are able to Drop direct on an Application (MAC). Other file formats just can be copied to Folders.
I think I'm not the only one who is looking for a full native file drop and I think chromium offers that already.

On chrome://downloads/ its possible to Drag any File on an Application (Mac).

Is there maybe a way to access this Drag Function in electron or can it become a part of?
Multi File Drag would be very nice too! :)

[chrome://downloads/ > js dragstart > chrome.send('drag', id)](https://code.google.com/p/chromium/codesearch#chromium/src/chrome/browser/resources/md_downloads/crisper.js&q=crisper.js&sq=package:chromium&type=cs&l=15751)

I have no knowledge, about cc++ but it found that... :D
[drag_download_item_views.cc](https://code.google.com/p/chromium/codesearch#chromium/src/chrome/browser/download/drag_download_item_views.cc&q=DragDownloadItem&sq=package:chromium&dr=CSs&l=31)
[md_downloads_dom_handler.cc](https://chromium.googlesource.com/chromium/src.git/+/master/chrome/browser/ui/webui/md_downloads/md_downloads_dom_handler.cc)

atom/browser/api/atom_api_web_contents.cc
PrintSettings settings = { false, false };
  if (args->Length() == 1 && !args->GetNext(&settings)) {
    args->ThrowError();
    return;
  }
  printing::PrintViewManagerBasic::FromWebContents(web_contents())->
      PrintNow(settings.silent, settings.print_background);
}
void WebContents::PrintToPDF(const base::DictionaryValue& setting,
                             const PrintToPDFCallback& callback) {
  printing::PrintPreviewMessageHandler::FromWebContents(web_contents())->
      PrintToPDF(setting, callback);
}
void WebContents::AddWorkSpace(mate::Arguments* args,
                               const base::FilePath& path) {
  if (path.empty()) {
    args->ThrowError("path cannot be empty");
    return;
  }
  DevToolsAddFileSystem(path);
}
void WebContents::RemoveWorkSpace(mate::Arguments* args,
                                  const base::FilePath& path) {
  if (path.empty()) {
    args->ThrowError("path cannot be empty");
    return;
  }
  DevToolsRemoveFileSystem(path);
}
void WebContents::Undo() {