> But by providing the API a browser that's downloading a 600MB ISO from a server that doesn't support resuming could indicate it doesn't want the network & storage systems to be suspended till it's finished. Perhaps this might be sufficient to block a timeout-triggered suspend but a user might still be allowed to force a suspend if required?
This reminds of the way KDE (and I suppose the others too) will stop you from logging off when you have unsaved changes. Indeed, you'd like to have a way to back off when the app tells you 'ongoing download: do you really want to stand-by?'