Engine Mismatch

Protect every paid visit

BotRefund combines browser, network, device, and behavior evidence to identify invalid traffic.

Best bot protection for your website

Detection approach

Engine mismatch detected via error stack trace format. The reported User-Agent claims one browser, but the JavaScript engine executes and formats errors like a completely different browser.

How this helps detect bots

Collect this signal alongside session context, request metadata, and other independent indicators. A single anomaly is a lead, not a verdict; corroborating anomalies make automated traffic more likely.

Legitimate traffic to consider

Users running legacy compatibility modes, niche custom browsers, or user-agent spoofing extensions for compatibility.

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BotRefund helps website owners identify suspicious visits, protect conversion data, and build evidence for invalid-click reviews.

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