I am investigating a persistent geolocation issue affecting Firefox, where the browser geolocation API returns a precise but incorrect location in the United States.
Actu… (lire la suite)
I am investigating a persistent geolocation issue affecting Firefox, where the browser geolocation API returns a precise but incorrect location in the United States.
Actual location:
United Kingdom (precise location not shared for privacy)
Incorrect location returned:
39.264542, -76.765924 (Catonsville, Maryland, USA)
Reported accuracy: approximately 185 meters around this incorrect point
This issue has been extensively tested and does not appear to be related to IP geolocation, system configuration, or local network setup.
Summary of findings:
Reproduced in Firefox and across other browsers:
Mozilla Firefox
Microsoft Edge
Google Chrome
Brave
Reproduced across multiple systems:
Windows 11
Windows Server 2025
Reproduced across multiple public IPs:
Static /29 allocation
BT dynamic IP (completely different address)
→ Same incorrect Maryland location returned in all cases
Wi-Fi vs Ethernet:
Wi-Fi (with SSID/location services) returns correct UK location
Ethernet consistently returns Maryland
→ Indicates fallback to provider-based geolocation rather than IP-based resolution
All standard IP geolocation sources are correct (UK):
ipinfo.io
ifconfig.co
DB-IP / BrowserLeaks IP lookup
RIPE allocation
Reverse DNS (BT Openworld)
Command-line and non-browser tests confirm correct UK location:
curl / PowerShell requests return UK consistently
No evidence of US routing, proxying, or DNS leakage
Critical observation:
Firefox geolocation (navigator.geolocation) returns:
Exact same coordinates every time
Same result across all browsers and machines
Consistent high-precision accuracy (~185 meters) around the incorrect Maryland location
Control comparison:
Pale Moon (more IP-based geolocation path) returns correct UK location
Conclusion:
This does not appear to be a traditional IP geolocation issue.
All IP-based systems resolve correctly to the UK. The incorrect result only occurs when using browser geolocation APIs.
Given:
The consistency across browsers and systems
The identical coordinates returned each time
The high-precision accuracy around the incorrect location
This strongly suggests a provider-side geolocation dataset issue.
Since Firefox uses Mozilla Location Services, I would like to confirm whether:
This result is coming from Mozilla Location Services directly, or from an upstream/shared dataset
Whether this type of persistent incorrect high-confidence location can be corrected or escalated within Mozilla’s geolocation system
Thank you.