User-Agent
Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:137.9) Gecko/20100101 Firefox/137.9
first seen 2026-08-17 22:38 · last seen 2026-08-18 08:40 · JSON
Distinct clients per day (last 30 days, peak 2/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 / client | Firefox 137.9 |
|---|---|
| Operating system | Windows 10.0 |
| Device class | desktop |
| 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 |
|---|---|
t13d1717h2_5b57614c22b0_3cbfd9057e0d Match?Exact match in Thumbprint's published controlled catalog captures: firefox 148.0.2, firefox 144.0.2, firefox 142.0.1, +6 more.The fingerprint page shows the full measured match list. More on the catalog. | 2 |
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)
| fingerprint | co-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. | 3 |
HTTP/2 frames (Akamai)
| fingerprint | co-occurrences |
|---|---|
1:65536;2:0;4:131072;5:16384|12517377|1:0:0:256|m,p,a,s | 2 |
1:65536;2:0;4:131072;5:16384|12517377|1:0:0:42|m,p,a,s | 1 |
TCP SYN (p0f)
| fingerprint | co-occurrences |
|---|---|
4:49+15:0:1460:mss*44,7:mss,sok,ts,nop,ws:df,id+:0 | 1 |
4:54+10:0:1460:32768,10:mss,nop,ws,sok,ts::0 | 1 |
4:53+11:0:8902:mss*7,12:mss,sok,ts,nop,ws:df,id+,ecn:0 | 1 |
TCP SYN (JA4T)
| fingerprint | co-occurrences |
|---|---|
64240_2-4-8-1-3_1460_7 | 1 |
32768_2-1-3-4-8_1460_10 | 1 |
62314_2-4-8-1-3_8902_12 | 1 |
Country
| fingerprint | co-occurrences |
|---|---|
NL · Netherlands | 2 |
SE · Sweden | 1 |
Network (ASN)
| fingerprint | co-occurrences |
|---|---|
AS210558 · 1337 Services GmbH | 1 |
AS215125 · Church of Cyberology | 1 |
AS214503 · QuxLabs AB | 1 |