It is weird. I suppose as a result of storing file content by hash only (without extension), then determining the Content-Type header based on the user-supplied

It is weird. I suppose as a result of storing file content by hash only (without extension), then determining the Content-Type header based on the user-supplied extension. Unless they're storing the original filename, they'll have to run through the binary data to determine file type. Crucially though, is they removed the DNS forward to the CDN. Which means they're actually storing .html files on those CDN servers. For ads, presumably, but it seems terribly silly to be storing .html files there at all.