I seriously love that I can take screenshots of specific elements in the page without having to drag a square. But uploading somewhere as soon as one presses the Save button (a bit misleading name, should say Upload) is a problem waiting to happen. At some point someone is gonna upload stuff they didn’t want to be uploaded and there no way to opt-out.
It would be very nice if you could use the Save button to actually Save the screenshot to my local disk and add an Upload or Share button if people want to do that.