A single static page served from an Azure Storage static website. It fetches its own URL and inspects the response headers to work out whether it reached you through Front Door or directly from storage.
Backend origin: sttestfdoy3xmzpcfsgug01.z6.web.core.windows.net — the storage account that actually served this response (baked in at deploy time, so each backend is identifiable).
| Served via Front Door | … |
|---|---|
x-azure-ref | … |
x-cache | … |
| Host | … |
Detection reads the x-azure-ref response header, which is present only when the response passed through Front Door.