ua-tracer
by Paul Kinlan
trace U6FSkGS4
what does a user agent actually fetch, follow & run?
Trace U6FSkGS4
First seen: 2026-08-29 22:08:16.209 UTC
User-Agent: YisouSpider
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.
| Received | Δ | Kind | Method | User-Agent |
|---|---|---|---|---|
| 2026-08-29 22:08:16.209 UTC | +0 ms | homepage | GET | YisouSpider |
request headers (21){
"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",
"sec-ch-ua": "\"HeadlessChrome\";v=\"141\", \"Not?A_Brand\";v=\"8\", \"Chromium\";v=\"141\"",
"sec-ch-ua-mobile": "?0",
"sec-ch-ua-platform": "\"Windows\"",
"sec-fetch-dest": "document",
"sec-fetch-mode": "navigate",
"sec-fetch-site": "none",
"sec-fetch-user": "?1",
"traceparent": "00-e4b05dfaea6b60d75c59e020d4f75bc5-050063507660f58d-01",
"tracestate": "",
"upgrade-insecure-requests": "1",
"user-agent": "YisouSpider",
"via": "HTTP/2 ams.vultr.prod.deno-cluster.net",
"x-deno-userspace-traceparent": "00-e4b05dfaea6b60d75c59e020d4f75bc5-8797b7de082a4cd4-01",
"x-deno-userspace-tracestate": ""
}
|
||||
| 2026-08-29 22:08:19.438 UTC | +3229 ms | iframe document | GET | YisouSpider |
request headers (22){
"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=U6FSkGS4",
"host": "uatracer.com",
"pragma": "no-cache",
"priority": "u=0, i",
"referer": "https://uatracer.com/",
"sec-ch-ua": "\"HeadlessChrome\";v=\"141\", \"Not?A_Brand\";v=\"8\", \"Chromium\";v=\"141\"",
"sec-ch-ua-mobile": "?0",
"sec-ch-ua-platform": "\"Windows\"",
"sec-fetch-dest": "iframe",
"sec-fetch-mode": "navigate",
"sec-fetch-site": "same-origin",
"traceparent": "00-440f5903d3e54c8bafffbf26ae19db3d-cb7626cf3dc3adfe-01",
"tracestate": "",
"upgrade-insecure-requests": "1",
"user-agent": "YisouSpider",
"via": "HTTP/2 ams.vultr.prod.deno-cluster.net",
"x-deno-userspace-traceparent": "00-440f5903d3e54c8bafffbf26ae19db3d-ee585a7d8d8984e0-01",
"x-deno-userspace-tracestate": ""
}
|
||||
| 2026-08-29 22:08:19.544 UTC | +3335 ms | prefetch | GET | YisouSpider |
request headers (15){
"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",
"accept-language": "zh-CN,zh;q=0.9",
"connection": "close",
"cookie": "ua-tracer-trace=U6FSkGS4",
"host": "uatracer.com",
"referer": "https://uatracer.com/",
"sec-ch-ua": "\"HeadlessChrome\";v=\"141\", \"Not?A_Brand\";v=\"8\", \"Chromium\";v=\"141\"",
"sec-ch-ua-mobile": "?0",
"sec-ch-ua-platform": "\"Windows\"",
"sec-purpose": "prefetch",
"traceparent": "00-096b534f08e6e1022ee68e77e02ae95c-6e85a50d6a0addc7-01",
"tracestate": "",
"user-agent": "YisouSpider",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net"
}
|
||||
| 2026-08-29 22:08:19.699 UTC | +3490 ms | CSS | GET | YisouSpider |
request headers (16){
"accept": "text/css,*/*;q=0.1",
"accept-encoding": "gzip,deflate,br",
"accept-language": "zh-CN,zh;q=0.9",
"connection": "close",
"cookie": "ua-tracer-trace=U6FSkGS4",
"host": "uatracer.com",
"referer": "https://uatracer.com/",
"sec-ch-ua": "\"HeadlessChrome\";v=\"141\", \"Not?A_Brand\";v=\"8\", \"Chromium\";v=\"141\"",
"sec-ch-ua-mobile": "?0",
"sec-ch-ua-platform": "\"Windows\"",
"traceparent": "00-dab598a9c349a314bc2718c7cb41b790-d1bd06bca9423924-01",
"tracestate": "",
"user-agent": "YisouSpider",
"via": "HTTP/1.1 ord.vultr.prod.deno-cluster.net",
"x-deno-userspace-traceparent": "00-dab598a9c349a314bc2718c7cb41b790-1a9bee5b74879b17-01",
"x-deno-userspace-tracestate": ""
}
|
||||
| 2026-08-29 22:08:19.731 UTC | +3522 ms | font (HTML) | GET | YisouSpider |
request headers (17){
"accept": "*/*",
"accept-encoding": "gzip,deflate,br",
"accept-language": "zh-CN,zh;q=0.9",
"connection": "close",
"cookie": "ua-tracer-trace=U6FSkGS4",
"host": "uatracer.com",
"origin": "https://uatracer.com",
"referer": "https://uatracer.com/",
"sec-ch-ua": "\"HeadlessChrome\";v=\"141\", \"Not?A_Brand\";v=\"8\", \"Chromium\";v=\"141\"",
"sec-ch-ua-mobile": "?0",
"sec-ch-ua-platform": "\"Windows\"",
"traceparent": "00-8a01f4de75f678b488f7c76b8e42f131-7324adb0ded07a12-01",
"tracestate": "",
"user-agent": "YisouSpider",
"via": "HTTP/1.1 ord.vultr.prod.deno-cluster.net",
"x-deno-userspace-traceparent": "00-8a01f4de75f678b488f7c76b8e42f131-04b945c0ca11177a-01",
"x-deno-userspace-tracestate": ""
}
|
||||
| 2026-08-29 22:08:19.940 UTC | +3731 ms | JS | GET | YisouSpider |
request headers (14){
"accept": "*/*",
"accept-encoding": "gzip,deflate,br",
"accept-language": "zh-CN,zh;q=0.9",
"connection": "close",
"cookie": "ua-tracer-trace=U6FSkGS4",
"host": "uatracer.com",
"referer": "https://uatracer.com/",
"sec-ch-ua": "\"HeadlessChrome\";v=\"141\", \"Not?A_Brand\";v=\"8\", \"Chromium\";v=\"141\"",
"sec-ch-ua-mobile": "?0",
"sec-ch-ua-platform": "\"Windows\"",
"traceparent": "00-ba18cf1977f94ee9b6d2b392edb3010b-4b4a7d8f1a8981b4-01",
"tracestate": "",
"user-agent": "YisouSpider",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net"
}
|
||||
| 2026-08-29 22:08:19.990 UTC | +3781 ms | ES module | GET | YisouSpider |
request headers (15){
"accept": "*/*",
"accept-encoding": "gzip,deflate,br",
"accept-language": "zh-CN,zh;q=0.9",
"connection": "close",
"cookie": "ua-tracer-trace=U6FSkGS4",
"host": "uatracer.com",
"origin": "https://uatracer.com",
"referer": "https://uatracer.com/",
"sec-ch-ua": "\"HeadlessChrome\";v=\"141\", \"Not?A_Brand\";v=\"8\", \"Chromium\";v=\"141\"",
"sec-ch-ua-mobile": "?0",
"sec-ch-ua-platform": "\"Windows\"",
"traceparent": "00-17c4c8f637eea5f196561a5907d9bb3c-f90f2738d06f5e25-01",
"tracestate": "",
"user-agent": "YisouSpider",
"via": "HTTP/1.1 ord.vultr.prod.deno-cluster.net"
}
|
||||
| 2026-08-29 22:08:21.143 UTC | +4934 ms | CSS @import (nested stylesheet) | GET | YisouSpider |
request headers (14){
"accept": "text/css,*/*;q=0.1",
"accept-encoding": "gzip,deflate,br",
"accept-language": "zh-CN,zh;q=0.9",
"connection": "close",
"cookie": "ua-tracer-trace=U6FSkGS4",
"host": "uatracer.com",
"referer": "https://uatracer.com/r/U6FSkGS4/YfYUs6sd/style.css",
"sec-ch-ua": "\"HeadlessChrome\";v=\"141\", \"Not?A_Brand\";v=\"8\", \"Chromium\";v=\"141\"",
"sec-ch-ua-mobile": "?0",
"sec-ch-ua-platform": "\"Windows\"",
"traceparent": "00-b6e7810256632fc1cf2d046885373dd4-5e5e62a7b14f2f19-01",
"tracestate": "",
"user-agent": "YisouSpider",
"via": "HTTP/1.1 ord.vultr.prod.deno-cluster.net"
}
|
||||
| 2026-08-29 22:08:22.384 UTC | +6175 ms | Reporting API report (POST) | POST | YisouSpider |
request headers (18){
"accept": "*/*",
"accept-encoding": "gzip,deflate,br",
"accept-language": "zh-CN,zh;q=0.9",
"connection": "close",
"content-length": "2086",
"content-type": "application/json",
"cookie": "ua-tracer-trace=U6FSkGS4",
"host": "uatracer.com",
"origin": "https://uatracer.com",
"referer": "https://uatracer.com/",
"sec-ch-ua": "\"HeadlessChrome\";v=\"141\", \"Not?A_Brand\";v=\"8\", \"Chromium\";v=\"141\"",
"sec-ch-ua-mobile": "?0",
"sec-ch-ua-platform": "\"Windows\"",
"traceparent": "00-b3557129a306e9a7d6978534508ee5e8-ab74e649bec66b3e-01",
"tracestate": "",
"user-agent": "YisouSpider",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net",
"x-report-body": "{\"source\":\"ReportingObserver\",\"reports\":[{\"type\":\"csp-violation\",\"url\":\"https://uatracer.com/\",\"body\":{\"sourceFile\":\"https://uatracer.com/\",\"lineNumber\":9,\"columnNumber\":0,\"documentURL\":\"https://uatracer.com/\",\"referrer\":\"\",\"blockedURL\":\"inline\",\"effectiveDirective\":\"style-src-elem\",\"originalPolicy\":\"style-src 'self'; report-uri /r/U6FSkGS4/YfYUs6sd/csp-report; report-to ua-tracer\",\"sample\":\"\",\"disposition\":\"report\",\"statusCode\":200}},{\"type\":\"csp-violation\",\"url\":\"https://uatracer.com/\",\"body\":{\"sourceFile\":\"https://uatracer.com/\",\"lineNumber\":243,\"columnNumber\":0,\"documentURL\":\"https://uatracer.com/\",\"referrer\":\"\",\"blockedURL\":\"inline\",\"effectiveDirective\":\"style-src-attr\",\"originalPolicy\":\"style-src 'self'; report-uri /r/U6FSkGS4/YfYUs6sd/csp-report; report-to ua-tracer\",\"sample\":\"\",\"disposition\":\"report\",\"statusCode\":200}},{\"type\":\"csp-violation\",\"url\":\"https://uatracer.com/\",\"body\":{\"sourceFile\":\"https://uatracer.com/\",\"lineNumber\":247,\"columnNumber\":0,\"documentURL\":\"https://uatracer.com/\",\"referrer\":\"\",\"blockedURL\":\"inline\",\"effectiveDirective\":\"style-src-attr\",\"originalPolicy\":\"style-src 'self'; report-uri /r/U6FSkGS4/YfYUs6sd/csp-report; report-to ua-tracer\",\"sample\":\"\",\"disposition\":\"report\",\"statusCode\":200}},{\"type\":\"csp-violation\",\"url\":\"https://uatracer.com/\",\"body\":{\"sourceFile\":\"https://uatracer.com/\",\"lineNumber\":755,\"columnNumber\":0,\"documentURL\":\"https://uatracer.com/\",\"referrer\":\"\",\"blockedURL\":\"inline\",\"effectiveDirective\":\"style-src-attr\",\"originalPolicy\":\"style-src 'self'; report-uri /r/U6FSkGS4/YfYUs6sd/csp-report; report-to ua-tracer\",\"sample\":\"\",\"disposition\":\"report\",\"statusCode\":200}},{\"type\":\"csp-violation\",\"url\":\"https://uatracer.com/\",\"body\":{\"sourceFile\":\"https://uatracer.com/r/U6FSkGS4/YfYUs6sd/main.js\",\"lineNumber\":45,\"columnNumber\":11,\"documentURL\":\"https://uatracer.com/\",\"referrer\":\"\",\"blockedURL\":\"inline\",\"effectiveDirective\":\"style-src-attr\",\"originalPolicy\":\"style-src 'self'; report-uri /r/U6FSkGS4/YfYUs6sd/csp-report; report-to ua-tracer\",\"sample\":\"\",\"disposition\":\"report\",\"statusCode\":200}}],\"ua\":\"YisouSpider\"}"
}
|
||||
| 2026-08-29 22:08:22.551 UTC | +6342 ms | CSP violation report (POST) | POST | YisouSpider |
request headers (20){
"accept": "*/*",
"accept-encoding": "gzip,deflate,br",
"accept-language": "zh-CN,zh;q=0.9",
"connection": "close",
"content-length": "293",
"content-type": "application/json",
"cookie": "ua-tracer-trace=U6FSkGS4",
"host": "uatracer.com",
"origin": "https://uatracer.com",
"referer": "https://uatracer.com/",
"sec-ch-ua": "\"HeadlessChrome\";v=\"141\", \"Not?A_Brand\";v=\"8\", \"Chromium\";v=\"141\"",
"sec-ch-ua-mobile": "?0",
"sec-ch-ua-platform": "\"Windows\"",
"traceparent": "00-583bc75caa5ab997c6361261158cf95c-79fa46838497ae62-01",
"tracestate": "",
"user-agent": "YisouSpider",
"via": "HTTP/1.1 ord.vultr.prod.deno-cluster.net",
"x-deno-userspace-traceparent": "00-583bc75caa5ab997c6361261158cf95c-66a394a993ce6bec-01",
"x-deno-userspace-tracestate": "",
"x-report-body": "{\"source\":\"securitypolicyviolation\",\"violatedDirective\":\"style-src-attr\",\"effectiveDirective\":\"style-src-attr\",\"blockedURI\":\"inline\",\"documentURI\":\"https://uatracer.com/\",\"disposition\":\"report\",\"lineNumber\":45,\"sourceFile\":\"https://uatracer.com/r/U6FSkGS4/YfYUs6sd/main.js\",\"ua\":\"YisouSpider\"}"
}
|
||||
| 2026-08-29 22:08:26.675 UTC | +10466 ms | CSS @font-face | GET | YisouSpider |
request headers (17){
"accept": "*/*",
"accept-encoding": "gzip,deflate,br",
"accept-language": "zh-CN,zh;q=0.9",
"connection": "close",
"cookie": "ua-tracer-trace=U6FSkGS4",
"host": "uatracer.com",
"origin": "https://uatracer.com",
"referer": "https://uatracer.com/r/U6FSkGS4/YfYUs6sd/style.css",
"sec-ch-ua": "\"HeadlessChrome\";v=\"141\", \"Not?A_Brand\";v=\"8\", \"Chromium\";v=\"141\"",
"sec-ch-ua-mobile": "?0",
"sec-ch-ua-platform": "\"Windows\"",
"traceparent": "00-897339345bce2523e0b5e7af20bc4045-fcec6d678c4ae2b7-01",
"tracestate": "",
"user-agent": "YisouSpider",
"via": "HTTP/1.1 ord.vultr.prod.deno-cluster.net",
"x-deno-userspace-traceparent": "00-897339345bce2523e0b5e7af20bc4045-963e656a7d605932-01",
"x-deno-userspace-tracestate": ""
}
|
||||
| 2026-08-29 22:08:28.475 UTC | +12266 ms | client timing POST | POST | YisouSpider |
request headers (19){
"accept": "*/*",
"accept-encoding": "gzip,deflate,br",
"accept-language": "zh-CN,zh;q=0.9",
"connection": "close",
"content-length": "2530",
"content-type": "application/json",
"cookie": "ua-tracer-trace=U6FSkGS4",
"host": "uatracer.com",
"origin": "https://uatracer.com",
"referer": "https://uatracer.com/",
"sec-ch-ua": "\"HeadlessChrome\";v=\"141\", \"Not?A_Brand\";v=\"8\", \"Chromium\";v=\"141\"",
"sec-ch-ua-mobile": "?0",
"sec-ch-ua-platform": "\"Windows\"",
"traceparent": "00-960866ed89dbeb740e3a1db7e337a0aa-9ec5fd3092226211-01",
"tracestate": "",
"user-agent": "YisouSpider",
"via": "HTTP/1.1 ord.vultr.prod.deno-cluster.net",
"x-deno-userspace-traceparent": "00-960866ed89dbeb740e3a1db7e337a0aa-13bec2ca8b384db5-01",
"x-deno-userspace-tracestate": ""
}
|
||||
| 2026-08-31 00:46:12.357 UTC | +95876148 ms | Open Graph image | GET | YisouSpider |
request headers (13){
"accept": "*/*",
"accept-encoding": "gzip",
"accept-language": "zh-CN,zh-TW;q=0.9,zh;q=0.8,en;q=0.7",
"connection": "Keep-Alive",
"host": "uatracer.com",
"interceptor": "9",
"referer": "https://uatracer.com/",
"shenma-host": "uatracer.com",
"shenma-ip": "69.67.170.170",
"traceparent": "00-8ada872507b6f877455eb698325fb05c-40cab414f1fd6bbd-01",
"tracestate": "",
"user-agent": "YisouSpider",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net"
}
|
||||
Client-side resource waterfall
Reported by performance.getEntriesByType('resource') after JS ran in the UA. This proves a real
browser-grade engine, not just a downloader.
| Resource | Initiator | Start | Duration | Timeline |
|---|---|---|---|---|
| link | 3980ms | 1387ms | ||
| link | 3980ms | 1869ms | ||
| link | 3980ms | 67ms | ||
| link | 3982ms | 2433ms | ||
| iframe | 4222ms | 873ms | ||
| img | 4222ms | 30ms | ||
| script | 4223ms | 1371ms | ||
| script | 4223ms | 1877ms | ||
| css | 5368ms | 1394ms | ||
| img | 6764ms | 30ms | ||
| css | 6764ms | 89ms | ||
| css | 6764ms | 5359ms | ||
| beacon | 6784ms | 1216ms | ||
| beacon | 6785ms | 1548ms | ||
| img | 6787ms | 38ms |