Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:159.0) Gecko/20100101 Firefox/159.0
first seen 2026-10-25 16:45 · last seen 2026-11-01 00:10 · JSON
Last 7 days (1 observations)
Distinct clients per day (last 30 days, peak 1/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 159.0
Operating system
macOS 10.15
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
t13d1517h2_8daaf6152771_3cbfd9057e0dMatch?Exact match in Thumbprint's published controlled catalog captures: firefox 155.0.1, firefox 154.0, firefox 156.0, +8 more.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.