Accepting files: namesOfPromisedFilesDroppedAtDestination opens Finder window

Question

I have a NSView to accept files from all the sources - local and remote. I use NSFilesPromisePboardType to accept remote files like images dragged from the browser. Here is the code I use to get dropped images to be copied into my folder:

- (BOOL)performDragOperation:(id <NSDraggingInfo>)sender
{
    NSPasteboard * pboard = [sender draggingPasteboard];
    NSDragOperation sourceDragMask = [sender draggingSourceOperationMask];

    if ([[pboard types] containsObject:NSFilesPromisePboardType])
    {
        [sender namesOfPromisedFilesDroppedAtDestination:_fileStorageFolder];
        return YES;
    }

    return NO;
}

And now I have noticed 2 issues:

1. "Looked for HFSPromises on the pasteboard, but found none." warning is printed into the debug console.
2. Finder opens a new window to show and highlight the newly downloaded file.

What is the correct way to receive files from browser without any warnings and Finder windows?

Answer 1

Answering my own question. There was nothing wrong with my code. It was the latest version of Google Chrome that opened Finder window after you drag&drop file from the browser to any location on your computer.

I found a bug-report for Google Chrome, tested Opera and Safari - everything is ok.

Sorry for bothering.