Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) HeadlessChrome/139.0.7258.5 Safari/537.36
first seen 2026-07-01 23:06 · last seen 2026-08-18 09:13 · JSON
Decomposed attributes
Browser / client
Headless Chrome 139.0.7258.5
Operating system
Linux x86_64
Device class
bot
Note
inferred from the self-declared string — a claim, not a measurement; compare with the wire fingerprints above
Co-observed signals
Signals from other families seen in the same observation. A fingerprint spread thinly across many lower-layer signatures is a classic inconsistency signal.
TLS ClientHello (JA4)
fingerprint
co-occurrences
t13d1516h2_8daaf6152771_d8a2da3f94cdMatch?Exact match in Thumbprint's published controlled catalog captures: chromium 149.0.7827.102, chrome 149.0.7827.102, chrome 149.0.7827.156, +25 more.The fingerprint page shows the full measured match list. More on the catalog.
4
q13d0311h3_55b375c5d22e_653d80c3fe9dMatch?Exact match in Thumbprint's published controlled catalog captures: chrome 150.0.7871.187, chromium 149.0.7827.102, chrome 149.0.7827.102, +52 more.The fingerprint page shows the full measured match list. More on the catalog.
q12_fcf871be5feeMatch?Exact match in Thumbprint's published controlled catalog captures: chromium 145.0.7632.6, chromium 143.0.7499.4, chromium 141.0.7390.37, +5 more.The fingerprint page shows the full measured match list. More on the catalog.
TLS ClientHello fingerprints observed from the same client via the beacon's correlation id on the other transport (e.g. this stack over TCP ↔ that stack over QUIC).