ua-tracer
by Paul Kinlan
ua-tracer
what does a user agent actually fetch, follow & run?
Trace j9Ubc6Vs
First seen: 2026-06-30 04:56:35.317 UTC
User-Agent: Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/148.0.7778.96 Mobile Safari/537.36 (compatible; GoogleOther)
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.
| Received | Δ | Kind | Method | User-Agent |
|---|---|---|---|---|
| 2026-06-30 04:56:35.317 UTC | +0 ms | homepage | GET | Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/148.0.7778.96 Mobile Safari/537.36 (compatible; GoogleOther) |
request headers (9){
"accept": "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8",
"accept-encoding": "gzip, deflate, br",
"connection": "keep-alive",
"from": "googlebot(at)googlebot.com",
"host": "uatracer.com",
"traceparent": "00-c17d41964f9d2c0a6197d3f959858c7c-ec0ae9efff656596-01",
"tracestate": "",
"user-agent": "Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/148.0.7778.96 Mobile Safari/537.36 (compatible; GoogleOther)",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net"
}
|
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| 2026-06-30 04:59:00.303 UTC | +144986 ms | ES module | GET | Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/148.0.7778.96 Mobile Safari/537.36 (compatible; GoogleOther) |
request headers (13){
"accept": "*/*",
"accept-encoding": "gzip, deflate, br",
"accept-language": "en-US",
"connection": "keep-alive",
"cookie": "ua-tracer-trace=j9Ubc6Vs",
"from": "googlebot(at)googlebot.com",
"host": "uatracer.com",
"origin": "https://uatracer.com",
"referer": "https://uatracer.com/",
"traceparent": "00-c8629e2c3a53512b08f192b6adc534a2-012b3384f78dc6cf-01",
"tracestate": "",
"user-agent": "Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/148.0.7778.96 Mobile Safari/537.36 (compatible; GoogleOther)",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net"
}
|
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| 2026-06-30 04:59:08.742 UTC | +153425 ms | CSS | GET | Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/148.0.7778.96 Mobile Safari/537.36 (compatible; GoogleOther) |
request headers (14){
"accept": "text/css,*/*;q=0.1",
"accept-encoding": "gzip, deflate, br",
"accept-language": "en-US",
"connection": "keep-alive",
"cookie": "ua-tracer-trace=j9Ubc6Vs",
"from": "googlebot(at)googlebot.com",
"host": "uatracer.com",
"referer": "https://uatracer.com/",
"traceparent": "00-31d60fdae0d294aeb390c7a1c3d5ef39-c52921fb8007ec71-01",
"tracestate": "",
"user-agent": "Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/148.0.7778.96 Mobile Safari/537.36 (compatible; GoogleOther)",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net",
"x-deno-userspace-traceparent": "00-31d60fdae0d294aeb390c7a1c3d5ef39-6536265f23bc82eb-01",
"x-deno-userspace-tracestate": ""
}
|
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| 2026-06-30 04:59:16.802 UTC | +161485 ms | CSS @import (nested stylesheet) | GET | Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/148.0.7778.96 Mobile Safari/537.36 (compatible; GoogleOther) |
request headers (12){
"accept": "text/css,*/*;q=0.1",
"accept-encoding": "gzip, deflate, br",
"accept-language": "en-US",
"connection": "keep-alive",
"cookie": "ua-tracer-trace=j9Ubc6Vs",
"from": "googlebot(at)googlebot.com",
"host": "uatracer.com",
"referer": "https://uatracer.com/r/j9Ubc6Vs/shHNvc2N/style.css",
"traceparent": "00-79d0509b0c9308d8c78f7e0803f87ac0-501e0ecfe29e28ef-01",
"tracestate": "",
"user-agent": "Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/148.0.7778.96 Mobile Safari/537.36 (compatible; GoogleOther)",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net"
}
|
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