Originally Posted by kovidgoyal
Why not do it at the end of metadata_downloaded? IIRC, that means the device is "fully connected"
The last thing metadata_downloaded does is call refresh_ondevice().
My thought was that if we are adding this signal, something that connects to the signal might want to know if the booklists have changed. There are other methods that change the booklist, for example books_uploaded and books_deleted, and both of these call refresh_ondevice at the right time.