Open Radar

 
Summary:
Photos app: when dragging photos to Finder while photo is still downloading, drag appears to do nothing until the download is finished

Steps to Reproduce:
Drag a photo (that has not yet been fully downloaded from iCloud) from Photos to the Desktop.

Expected Results:
An icon appears immediately at the drop location, titled something like MyPhoto.download, with a progress bar on. When the download finishes, this icon turns into the requested file.

Actual Results:
It appears initially that the drag has not worked. Then, the photo shows up much later, when the download is complete. (This is especially noticeable on a slow connection.)

Notes:
Note that (assuming the Finder window in question is in icon view and unsorted) it is very important that both the temporary 'download' icon and the final file icon appear in the location where the mouse was released, rather than just slotting in anywhere there is space.