ua-tracer by Paul Kinlan

trace WKluruvQ

ua-tracer

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

← all traces

Trace WKluruvQ

First seen: 2026-07-05 15:11:45.962 UTC
User-Agent: Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)
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
2026-07-05 15:11:45.962 UTC +0 ms homepage GET Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)
request headers (14) 
{
  "accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/heif,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,zh-CN;q=0.9",
  "host": "uatracer.com",
  "priority": "u=0, i",
  "sec-fetch-dest": "document",
  "sec-fetch-mode": "navigate",
  "sec-fetch-site": "none",
  "sec-fetch-user": "?1",
  "traceparent": "00-6d46a4a6bfe6c8c693bb5821bfc853f7-03f69f1fe2ce20f3-01",
  "tracestate": "",
  "upgrade-insecure-requests": "1",
  "user-agent": "Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-05 15:11:48.429 UTC +2467 ms CSS GET Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)
request headers (14) 
{
  "accept": "text/css,*/*;q=0.1",
  "accept-encoding": "gzip, deflate, br, zstd",
  "accept-language": "zh,zh-CN;q=0.9",
  "cookie": "ua-tracer-trace=WKluruvQ",
  "host": "uatracer.com",
  "priority": "u=0",
  "referer": "https://uatracer.com/",
  "sec-fetch-dest": "style",
  "sec-fetch-mode": "no-cors",
  "sec-fetch-site": "same-origin",
  "traceparent": "00-409edc45dff8d22bc7fd40d16b12eb59-c884731d26e45c63-01",
  "tracestate": "",
  "user-agent": "Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-05 15:11:48.613 UTC +2651 ms preload (image) GET Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)
request headers (15) 
{
  "accept": "image/heif,image/avif,image/webp,image/apng,image/svg+xml,image/*,*/*;q=0.8",
  "accept-encoding": "identity",
  "accept-language": "zh,zh-CN;q=0.9",
  "cookie": "ua-tracer-trace=WKluruvQ",
  "host": "uatracer.com",
  "priority": "i",
  "range": "bytes=0-499",
  "referer": "https://uatracer.com/",
  "sec-fetch-dest": "image",
  "sec-fetch-mode": "no-cors",
  "sec-fetch-site": "same-origin",
  "traceparent": "00-bf25f68e33df906840621713650753d9-ad1eb66a57377f1d-01",
  "tracestate": "",
  "user-agent": "Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-05 15:11:49.502 UTC +3540 ms iframe document GET Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)
request headers (15) 
{
  "accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/heif,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,zh-CN;q=0.9",
  "cookie": "ua-tracer-trace=WKluruvQ",
  "host": "uatracer.com",
  "priority": "u=0, i",
  "referer": "https://uatracer.com/",
  "sec-fetch-dest": "iframe",
  "sec-fetch-mode": "navigate",
  "sec-fetch-site": "same-origin",
  "traceparent": "00-a701393e2dc2db4f3cacc467bebb971c-a66e5f2478dcadeb-01",
  "tracestate": "",
  "upgrade-insecure-requests": "1",
  "user-agent": "Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-05 15:11:49.750 UTC +3788 ms JS GET Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)
request headers (14) 
{
  "accept": "*/*",
  "accept-encoding": "gzip, deflate, br, zstd",
  "accept-language": "zh,zh-CN;q=0.9",
  "cookie": "ua-tracer-trace=WKluruvQ",
  "host": "uatracer.com",
  "priority": "u=1",
  "referer": "https://uatracer.com/",
  "sec-fetch-dest": "script",
  "sec-fetch-mode": "no-cors",
  "sec-fetch-site": "same-origin",
  "traceparent": "00-c61c6ca1a0a5d1b958130ee4fd772bad-eaf792b7e1949308-01",
  "tracestate": "",
  "user-agent": "Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-05 15:11:49.784 UTC +3822 ms image GET Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)
request headers (15) 
{
  "accept": "image/heif,image/avif,image/webp,image/apng,image/svg+xml,image/*,*/*;q=0.8",
  "accept-encoding": "identity",
  "accept-language": "zh,zh-CN;q=0.9",
  "cookie": "ua-tracer-trace=WKluruvQ",
  "host": "uatracer.com",
  "priority": "i",
  "range": "bytes=0-499",
  "referer": "https://uatracer.com/",
  "sec-fetch-dest": "image",
  "sec-fetch-mode": "no-cors",
  "sec-fetch-site": "same-origin",
  "traceparent": "00-6ed3e5af8d4fb5cfbdcdaff6f15b40c1-7a1d41887ba10a03-01",
  "tracestate": "",
  "user-agent": "Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-05 15:11:49.787 UTC +3825 ms ES module GET Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)
request headers (15) 
{
  "accept": "*/*",
  "accept-encoding": "gzip, deflate, br, zstd",
  "accept-language": "zh,zh-CN;q=0.9",
  "cookie": "ua-tracer-trace=WKluruvQ",
  "host": "uatracer.com",
  "origin": "https://uatracer.com",
  "priority": "u=1",
  "referer": "https://uatracer.com/",
  "sec-fetch-dest": "script",
  "sec-fetch-mode": "cors",
  "sec-fetch-site": "same-origin",
  "traceparent": "00-17be8667996924e016aa6b05195e2000-bde5e8603afe5248-01",
  "tracestate": "",
  "user-agent": "Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-05 15:11:49.954 UTC +3992 ms CSS @import (nested stylesheet) GET Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)
request headers (14) 
{
  "accept": "text/css,*/*;q=0.1",
  "accept-encoding": "gzip, deflate, br, zstd",
  "accept-language": "zh,zh-CN;q=0.9",
  "cookie": "ua-tracer-trace=WKluruvQ",
  "host": "uatracer.com",
  "priority": "u=0",
  "referer": "https://uatracer.com/r/WKluruvQ/6hAN5wRS/style.css",
  "sec-fetch-dest": "style",
  "sec-fetch-mode": "no-cors",
  "sec-fetch-site": "same-origin",
  "traceparent": "00-e4a8d694bd0b5f7c7f9b6ef30e01040e-67c5e5fc7076b5b0-01",
  "tracestate": "",
  "user-agent": "Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-05 15:11:50.387 UTC +4425 ms image inside iframe GET Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)
request headers (15) 
{
  "accept": "image/heif,image/avif,image/webp,image/apng,image/svg+xml,image/*,*/*;q=0.8",
  "accept-encoding": "identity",
  "accept-language": "zh,zh-CN;q=0.9",
  "cookie": "ua-tracer-trace=WKluruvQ",
  "host": "uatracer.com",
  "priority": "i",
  "range": "bytes=0-499",
  "referer": "https://uatracer.com/r/WKluruvQ/6hAN5wRS/iframe",
  "sec-fetch-dest": "image",
  "sec-fetch-mode": "no-cors",
  "sec-fetch-site": "same-origin",
  "traceparent": "00-f4d9eb861736e549741ca756cd286ac4-a8c16dc57d1754a7-01",
  "tracestate": "",
  "user-agent": "Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-05 15:11:52.037 UTC +6075 ms CSS background-image GET Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)
request headers (15) 
{
  "accept": "image/heif,image/avif,image/webp,image/apng,image/svg+xml,image/*,*/*;q=0.8",
  "accept-encoding": "identity",
  "accept-language": "zh,zh-CN;q=0.9",
  "cookie": "ua-tracer-trace=WKluruvQ",
  "host": "uatracer.com",
  "priority": "i",
  "range": "bytes=0-499",
  "referer": "https://uatracer.com/r/WKluruvQ/6hAN5wRS/style.css",
  "sec-fetch-dest": "image",
  "sec-fetch-mode": "no-cors",
  "sec-fetch-site": "same-origin",
  "traceparent": "00-9f003e6f766532242aa05811c6c8c17b-caa760369fbd6942-01",
  "tracestate": "",
  "user-agent": "Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-05 15:11:52.251 UTC +6289 ms JS executed beacon GET Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)
request headers (15) 
{
  "accept": "image/heif,image/avif,image/webp,image/apng,image/svg+xml,image/*,*/*;q=0.8",
  "accept-encoding": "identity",
  "accept-language": "zh,zh-CN;q=0.9",
  "cookie": "ua-tracer-trace=WKluruvQ",
  "host": "uatracer.com",
  "priority": "i",
  "range": "bytes=0-499",
  "referer": "https://uatracer.com/",
  "sec-fetch-dest": "image",
  "sec-fetch-mode": "no-cors",
  "sec-fetch-site": "same-origin",
  "traceparent": "00-38d7cfcaee35f931ddc9b97925692d0f-8c066dcff775e4fc-01",
  "tracestate": "",
  "user-agent": "Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-05 15:11:52.255 UTC +6293 ms ES module executed GET Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)
request headers (15) 
{
  "accept": "image/heif,image/avif,image/webp,image/apng,image/svg+xml,image/*,*/*;q=0.8",
  "accept-encoding": "identity",
  "accept-language": "zh,zh-CN;q=0.9",
  "cookie": "ua-tracer-trace=WKluruvQ",
  "host": "uatracer.com",
  "priority": "i",
  "range": "bytes=0-499",
  "referer": "https://uatracer.com/",
  "sec-fetch-dest": "image",
  "sec-fetch-mode": "no-cors",
  "sec-fetch-site": "same-origin",
  "traceparent": "00-4a5e8d86f257ded9eb6f8d0368dfed9c-c32714fb41d1e906-01",
  "tracestate": "",
  "user-agent": "Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; https://zhanzhang.toutiao.com/)",
  "via": "HTTP/2 ams.vultr.prod.deno-cluster.net"
}
2026-07-05 19:42:02.362 UTC +16216400 ms iframe document GET Mozilla/5.0 (iPhone; CPU iPhone OS 13_2_3 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.0.3 Mobile/15E148 Safari/604.1
request headers (12) 
{
  "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",
  "accept-language": "zh-CN,zh;q=0.9,en-US;q=0.8,en;q=0.7",
  "cache-control": "no-cache",
  "connection": "keep-alive, close",
  "host": "uatracer.com",
  "pragma": "no-cache",
  "traceparent": "00-d770238c01035117995263fa6665be4c-cc3fc70aaf076a49-01",
  "tracestate": "",
  "upgrade-insecure-requests": "1",
  "user-agent": "Mozilla/5.0 (iPhone; CPU iPhone OS 13_2_3 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.0.3 Mobile/15E148 Safari/604.1",
  "via": "HTTP/1.1 ord.vultr.prod.deno-cluster.net"
}
2026-07-07 01:45:33.350 UTC +124427388 ms image GET Mozilla/5.0 (compatible; crawler)
request headers (9) 
{
  "accept": "*/*",
  "accept-encoding": "gzip, deflate",
  "accept-language": "en-US",
  "connection": "keep-alive",
  "host": "uatracer.com",
  "traceparent": "00-f7bf66b12655412d1422073a7f68b236-92fc2ae98f67cdeb-01",
  "tracestate": "",
  "user-agent": "Mozilla/5.0 (compatible; crawler)",
  "via": "HTTP/1.1 ord.vultr.prod.deno-cluster.net"
}

Client-side resource waterfall

JS executed (beacon hit) but no resource-timing payload was posted (UA may block sendBeacon/fetch or strip the body).