I see. Yeah I had cookies disabled in both browsers I tried. Trying using a narrow viewport does load fine, although it's possible to have dual-purpose desktop and mobile styling in a single SVG using media queries, which I've done before (not sure how your desktop version differs though).

The reason why we need cookies is to deliver different versions depending on the platform.

By default, the mobile version is served. If it turns out that the request came from a big screen, a cookie is set and the page is reloaded.

From then on, the cookie is used and the big-screen version is sent by default.

The point is just to have a single address for each page but to deliver appropriate content depending on the platform.