It should open in your browser as an image. It does in mine – on whatever browser I use. I’m not sure what you mean by the term “…but not as a file”.
Once upon a time browsers had settings to allow you to download immediately, but that generally regarded as an unsafe practice now and therefore not allowed in modern browsers.
I think that is a good thing. Now it opens full size in a new tab (or window – again depending on browser settings), and you can right-click to choose if to download / save it, and where to.