ua-tracer by Paul Kinlan

ua-tracer

what does a user agent actually fetch, follow & run?

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Trace IjNwfVV3

First seen: 2026-07-02 18:55:20.167 UTC
User-Agent: Mozilla/5.0 (compatible; SvelteKit-FYI/1.0; +https://sveltekit.fyi)
Bot verification: Not a known bot (no IP-range check applies).

What this user agent did

Directly-referenced assets:

✗ fetched CSS ✓ fetched JS ✗ fetched image ✗ fetched font (HTML)

Document-level link hints:

✗ fetched favicon ✗ fetched apple-touch-icon ✗ fetched web manifest ✗ fetched preload ✗ fetched prefetch

Second-level follows (proves it parsed the linking file):

✗ followed CSS background-image ✗ followed CSS @font-face ✗ followed manifest icon ✗ followed CSS @import

Frames (does it descend into iframes?):

✗ fetched iframe document ✗ descended into iframe (loaded inner image)

Reporting (a report-only CSP is violated by inline styles; reports can arrive via HTTP headers with no JS, or via in-page beacons):

✗ sent a CSP/Reporting report (any path) ✗ delivered via report-uri/Report-To header (no JS) ✗ delivered via in-page beacon (securitypolicyviolation / ReportingObserver)

Social embed (Open Graph / Twitter card images):

✗ fetched og:image ✗ fetched twitter:image

JavaScript execution:

✗ EXECUTED classic JS ✗ EXECUTED ES module ✗ posted client timing

Server-side request waterfall

Every request the server received for this trace, in receive order. +ms is the delta from the homepage request.

ReceivedΔKindMethodUser-Agent
2026-07-02 18:55:20.167 UTC +0 ms homepage GET Mozilla/5.0 (compatible; SvelteKit-FYI/1.0; +https://sveltekit.fyi)
request headers (10) 
{
  "accept": "text/html,application/xhtml+xml",
  "accept-encoding": "gzip",
  "accept-language": "en",
  "host": "uatracer.com",
  "traceparent": "00-7e76b1b57f5ba98ea3d5a96bfdc8d6c9-e2c8b152c4f19807-01",
  "tracestate": "",
  "user-agent": "Mozilla/5.0 (compatible; SvelteKit-FYI/1.0; +https://sveltekit.fyi)",
  "via": "HTTP/2 ord.vultr.prod.deno-cluster.net",
  "x-deno-userspace-traceparent": "00-7e76b1b57f5ba98ea3d5a96bfdc8d6c9-b44c7578535e48cb-01",
  "x-deno-userspace-tracestate": ""
}
2026-07-02 18:55:21.055 UTC +888 ms JS GET Mozilla/5.0 (compatible; SvelteKit-FYI/1.0; +https://sveltekit.fyi)
request headers (9) 
{
  "accept": "application/javascript, text/javascript, */*; q=0.01",
  "accept-encoding": "gzip",
  "host": "uatracer.com",
  "traceparent": "00-bf4ba8266c709aa1f66df9a21fcbf655-3125732e5d14d86d-01",
  "tracestate": "",
  "user-agent": "Mozilla/5.0 (compatible; SvelteKit-FYI/1.0; +https://sveltekit.fyi)",
  "via": "HTTP/2 ord.vultr.prod.deno-cluster.net",
  "x-deno-userspace-traceparent": "00-bf4ba8266c709aa1f66df9a21fcbf655-11143f1d9be8aba8-01",
  "x-deno-userspace-tracestate": ""
}
2026-07-02 18:55:21.066 UTC +899 ms ES module GET Mozilla/5.0 (compatible; SvelteKit-FYI/1.0; +https://sveltekit.fyi)
request headers (9) 
{
  "accept": "application/javascript, text/javascript, */*; q=0.01",
  "accept-encoding": "gzip",
  "host": "uatracer.com",
  "traceparent": "00-c7819295a7579f757e5d624ddd5ffc4e-6421454283b5358b-01",
  "tracestate": "",
  "user-agent": "Mozilla/5.0 (compatible; SvelteKit-FYI/1.0; +https://sveltekit.fyi)",
  "via": "HTTP/2 ord.vultr.prod.deno-cluster.net",
  "x-deno-userspace-traceparent": "00-c7819295a7579f757e5d624ddd5ffc4e-99bd2d0b53af41af-01",
  "x-deno-userspace-tracestate": ""
}