Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:138.0) Gecko/20100101 Firefox/138.0
first seen 2026-08-01 04:38 · last seen 2026-10-25 19:46 · 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 138.0
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
t13d131100_f57a46bbacb6_ab7e3b40a677Match?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.
11ec,001d,0017,0018,0019Match?Exact match in Thumbprint's published controlled catalog captures: firefox 158.0.1, firefox 157.0, firefox 157.0.1, +5 more.The fingerprint page shows the full measured match list. More on the catalog.