Pasting from a file browser and HTML5 Clipboard API

I'm trying to add an image paste function to my web application, using the standard routine:

$('textarea').on('paste', function (ev) {
    var clipboardData = ev.originalEvent.clipboardData;

    $.each(clipboardData.items, function (i, item) {
        if (item.type.indexOf("image") !== -1) {
            var reader = new FileReader();

            reader.readAsDataURL(item.getAsFile());
            reader.addEventListener('loadend', ...);
            ...
        }
    });
});

The full sample can be found here: http://ift.tt/1HjSsOD

It works correctly when I copy & paste an image from an image viewer software, but when I'm trying to do the same thing using a file browser (e.g. Finder on Mac or Nautilus on Linux) as a result I get only a text string with the file path or even an image with file type icon instead of an original file.

Is there any way to handle pastes from a file browser properly?