ua-tracer by Paul Kinlan

trace stSPCbuC

ua-tracer

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

← all traces

Trace stSPCbuC

First seen: 2026-07-13 19:56:45.665 UTC
User-Agent: pc
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
2026-07-13 19:56:45.665 UTC +0 ms homepage GET pc
request headers (20) 
{
  "accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7",
  "accept-encoding": "gzip, deflate, br, zstd",
  "accept-language": "zh-CN",
  "cache-control": "no-cache",
  "host": "uatracer.com",
  "pragma": "no-cache",
  "priority": "u=0, i",
  "referer": "http://m.baidu.com/s?wd=elsegpe",
  "sec-ch-ua": "\"Chromium\";v=\"134\", \"Not:A-Brand\";v=\"24\", \"HeadlessChrome\";v=\"134\"",
  "sec-ch-ua-mobile": "?1",
  "sec-ch-ua-platform": "\"Windows\"",
  "sec-fetch-dest": "document",
  "sec-fetch-mode": "navigate",
  "sec-fetch-site": "none",
  "sec-fetch-user": "?1",
  "traceparent": "00-c5699282cd4a1daaac51c660382cd0cf-9779de029ace39e2-01",
  "tracestate": "",
  "upgrade-insecure-requests": "1",
  "user-agent": "pc",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-13 19:56:54.215 UTC +8550 ms prefetch GET pc
request headers (20) 
{
  "accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7",
  "accept-encoding": "gzip, deflate, br, zstd",
  "accept-language": "zh-CN,zh",
  "cache-control": "no-cache",
  "cookie": "ua-tracer-trace=stSPCbuC",
  "host": "uatracer.com",
  "pragma": "no-cache",
  "priority": "u=4, i",
  "purpose": "prefetch",
  "referer": "http://m.baidu.com/s?wd=elsegpe",
  "sec-ch-ua": "\"Chromium\";v=\"134\", \"Not:A-Brand\";v=\"24\", \"HeadlessChrome\";v=\"134\"",
  "sec-ch-ua-mobile": "?1",
  "sec-ch-ua-platform": "\"Windows\"",
  "sec-fetch-dest": "empty",
  "sec-fetch-mode": "no-cors",
  "sec-fetch-site": "same-origin",
  "traceparent": "00-cfab1f03c18e17aa5a92c34f0301a10a-58c0aa64b02f8bc4-01",
  "tracestate": "",
  "user-agent": "pc",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-13 19:56:54.273 UTC +8608 ms iframe document GET pc
request headers (20) 
{
  "accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7",
  "accept-encoding": "gzip, deflate, br, zstd",
  "accept-language": "zh-CN",
  "cache-control": "no-cache",
  "cookie": "ua-tracer-trace=stSPCbuC",
  "host": "uatracer.com",
  "pragma": "no-cache",
  "priority": "u=0, i",
  "referer": "https://uatracer.com/",
  "sec-ch-ua": "\"Chromium\";v=\"134\", \"Not:A-Brand\";v=\"24\", \"HeadlessChrome\";v=\"134\"",
  "sec-ch-ua-mobile": "?1",
  "sec-ch-ua-platform": "\"Windows\"",
  "sec-fetch-dest": "iframe",
  "sec-fetch-mode": "navigate",
  "sec-fetch-site": "same-origin",
  "traceparent": "00-3b4693c7aa1c205658d68a5ceb270369-5d7fe5620c8786aa-01",
  "tracestate": "",
  "upgrade-insecure-requests": "1",
  "user-agent": "pc",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-13 19:56:54.288 UTC +8623 ms JS GET pc
request headers (19) 
{
  "accept": "*/*",
  "accept-encoding": "gzip, deflate, br, zstd",
  "accept-language": "zh-CN,zh",
  "cache-control": "no-cache",
  "cookie": "ua-tracer-trace=stSPCbuC",
  "host": "uatracer.com",
  "pragma": "no-cache",
  "priority": "u=1",
  "referer": "http://m.baidu.com/s?wd=elsegpe",
  "sec-ch-ua": "\"Chromium\";v=\"134\", \"Not:A-Brand\";v=\"24\", \"HeadlessChrome\";v=\"134\"",
  "sec-ch-ua-mobile": "?1",
  "sec-ch-ua-platform": "\"Windows\"",
  "sec-fetch-dest": "script",
  "sec-fetch-mode": "no-cors",
  "sec-fetch-site": "same-origin",
  "traceparent": "00-60169d29dd4eb384e56c00aa6503d187-84413ce422465a84-01",
  "tracestate": "",
  "user-agent": "pc",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-13 19:56:54.290 UTC +8625 ms ES module GET pc
request headers (20) 
{
  "accept": "*/*",
  "accept-encoding": "gzip, deflate, br, zstd",
  "accept-language": "zh-CN,zh",
  "cache-control": "no-cache",
  "cookie": "ua-tracer-trace=stSPCbuC",
  "host": "uatracer.com",
  "origin": "https://uatracer.com",
  "pragma": "no-cache",
  "priority": "u=1",
  "referer": "http://m.baidu.com/s?wd=elsegpe",
  "sec-ch-ua": "\"Chromium\";v=\"134\", \"Not:A-Brand\";v=\"24\", \"HeadlessChrome\";v=\"134\"",
  "sec-ch-ua-mobile": "?1",
  "sec-ch-ua-platform": "\"Windows\"",
  "sec-fetch-dest": "script",
  "sec-fetch-mode": "cors",
  "sec-fetch-site": "same-origin",
  "traceparent": "00-4ab8d803703268c22bd36edad8db7834-4e34d4c550c3130e-01",
  "tracestate": "",
  "user-agent": "pc",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-13 21:14:56.562 UTC +4690897 ms iframe document GET pc
request headers (20) 
{
  "accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7",
  "accept-encoding": "gzip, deflate, br, zstd",
  "accept-language": "zh-CN",
  "cache-control": "no-cache",
  "host": "uatracer.com",
  "pragma": "no-cache",
  "priority": "u=0, i",
  "referer": "http://m.baidu.com/s?wd=engineercz3",
  "sec-ch-ua": "\"Chromium\";v=\"134\", \"Not:A-Brand\";v=\"24\", \"HeadlessChrome\";v=\"134\"",
  "sec-ch-ua-mobile": "?1",
  "sec-ch-ua-platform": "\"Windows\"",
  "sec-fetch-dest": "document",
  "sec-fetch-mode": "navigate",
  "sec-fetch-site": "none",
  "sec-fetch-user": "?1",
  "traceparent": "00-5efad0ceb099d8158d2a868def17f9f6-c6ee170385d0be7a-01",
  "tracestate": "",
  "upgrade-insecure-requests": "1",
  "user-agent": "pc",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}