User-Agent

Mozilla/5.0 (X11; Linux x86_64; rv:121.0) Gecko/20100101 Firefox/121.0

first seen 2026-07-01 14:32 · last seen 2026-10-31 04:21 · JSON

Last 7 days (103 observations)

Distinct clients per day (last 30 days, peak 63/day)

Distinct clients are counted by IP-hash per complete UTC day — unlike observation counts this is insensitive to one chatty client, but NAT merges clients and address rotation splits them.

Decomposed attributes

Browser / clientFirefox 121.0
Operating systemLinux x86_64
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
t13d131100_f57a46bbacb6_ab7e3b40a677 Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.26.6, go-net/http 1.26.5, go-net/http 1.26.4.The fingerprint page shows the full measured match list. More on the catalog.103
t13d1312h1_f57a46bbacb6_ab7e3b40a67712
t13d1011h2_61a7ad8aa9b6_3fcd1a44f3e3 Match?Exact match in Thumbprint's published controlled catalog captures: rust-reqwest 0.12.28.The fingerprint page shows the full measured match list. More on the catalog.1
t13d311000_e8f1e7e78f70_1f22a2ca17c41
t13d301100_1d37bd780c83_8e6e362c5eac1

HTTP request (JA4H)

fingerprintco-occurrences
ge11nr16zhtw_3dfdba18536b_000000000000_00000000000015
ge11nr16frfr_3dfdba18536b_000000000000_00000000000013
ge11nr16zhcn_3dfdba18536b_000000000000_00000000000011
ge11nr16dede_3dfdba18536b_000000000000_00000000000010
ge11nr16enus_3dfdba18536b_000000000000_0000000000009
ge11nr16engb_3dfdba18536b_000000000000_0000000000009
ge11nr15dede_944d72baa157_000000000000_0000000000008
ge11nr05enus_900748f1e0f3_000000000000_0000000000007
ge11nr15frfr_944d72baa157_000000000000_0000000000007
ge11nr15zhtw_944d72baa157_000000000000_0000000000007

HTTP/2 frames (Akamai)

fingerprintco-occurrences
2:0;4:2097152;5:16384;6:16384|5177345|0|m,s,a,p Match?Exact match in Thumbprint's published controlled catalog captures: rust-reqwest 0.12.28, rust-reqwest 0.13.5, rust-reqwest 0.13.4, +4 more.The fingerprint page shows the full measured match list. More on the catalog.1

TCP SYN (p0f)

fingerprintco-occurrences
4:46+18:0:1440:65535,6:mss,sok,ts,nop,ws:df,id+:04
4:51+13:0:1460:mss*29,11:mss,sok,ts,nop,ws:df,id+:03
4:49+15:0:1460:mss*44,7:mss,sok,ts,nop,ws:df,id+:03
4:47+17:0:1440:65535,8:mss,sok,ts,nop,ws:df,id+:03
4:44+20:0:1460:65535,6:mss,sok,ts,nop,ws:df,id+:03
4:51+13:0:1460:mss*29,9:mss,sok,ts,nop,ws:df,id+:02
4:46+18:0:1460:mss*44,7:mss,sok,ts,nop,ws:df,id+:02
4:56+8:0:1460:mss*29,11:mss,sok,ts,nop,ws:df,id+:02
4:47+17:0:1412:mss*44,7:mss,sok,ts,nop,ws:df,id+:02
4:45+19:0:1440:65535,8:mss,sok,ts,nop,ws:df,id+:02

TCP SYN (JA4T)

fingerprintco-occurrences
64240_2-4-8-1-3_1460_710
65535_2-4-8-1-3_1412_69
65535_2-4-8-1-3_1412_88
65535_2-4-8-1-3_1440_68
64240_2-4-8-1-3_1412_77
64240_2-4-8-1-3_1452_77
65535_2-4-8-1-3_1460_66
65535_2-4-8-1-3_1440_86
64240_2-4-8-1-3_1400_75
42340_2-4-8-1-3_1460_115

Country

fingerprintco-occurrences
BR · Brazil28
AR · Argentina11
PK · Pakistan8
NL · Netherlands7
BD · Bangladesh7
CO · Colombia7
US · United States6
MX · Mexico6
MA · Morocco5
VE · Venezuela4

Network (ASN)

fingerprintco-occurrences
AS48090 · TECHOFF SRV LIMITED7
AS142430 · DIGI VPS3
AS26599 · TELEFÔNICA BRASIL S.A3
AS7922 · Comcast Cable Communications, LLC2
AS36884 · Wana Corporate2
AS10620 · Telmex Colombia S.A.2
AS17072 · TOTAL PLAY TELECOMUNICACIONES, S.A.P.I. DE C.V.2
AS328471 · HERO TELECOMS (PTY) LTD2
AS22927 · Telefonica de Argentina2
AS45669 · JPL /LDI IP TRANSIT2

TLS supported groups

fingerprintco-occurrences
11ec,001d,0017,0018,0019 Match?Exact match in Thumbprint's published controlled catalog captures: firefox 157.0.1, firefox-esr 153.5.1esr, firefox 158.0.1, +3 more.The fingerprint page shows the full measured match list. More on the catalog.103
001d,0017,0018 Match?Exact match in Thumbprint's published controlled catalog captures: rust-reqwest 0.12.28, rust-reqwest 0.11.27, powershell 7.6.8, +1 more.The fingerprint page shows the full measured match list. More on the catalog.1