User-Agent

Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:137.3) Gecko/20100101 Firefox/137.3

first seen 2026-08-18 15:16 · last seen 2026-08-18 15:16 · JSON

Decomposed attributes

Browser / clientFirefox 137.3
Operating systemmacOS 10.15
Device classdesktop
Noteinferred 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)

fingerprintco-occurrences
t13d1716h2_5b57614c22b0_eeeea6562960 Match?Exact match in Thumbprint's published controlled catalog captures: firefox 132.0, firefox 134.0.The fingerprint page shows the full measured match list. More on the catalog.1

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn11enus_3901d4197baf_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: firefox 154.0, firefox 152.0.5, firefox 153.0.1, +3 more.The fingerprint page shows the full measured match list. More on the catalog.1

HTTP/2 frames (Akamai)

fingerprintco-occurrences
1:65536;2:0;4:131072;5:16384|12517377|1:0:0:256|m,p,a,s1

TCP SYN (p0f)

fingerprintco-occurrences
4:54+10:0:1460:32768,10:mss,nop,ws,sok,ts::01

TCP SYN (JA4T)

fingerprintco-occurrences
32768_2-1-3-4-8_1460_101

Country

fingerprintco-occurrences
NL · Netherlands1

Network (ASN)

fingerprintco-occurrences
AS215125 · Church of Cyberology1