Firefox network prediction must be disabled.

If network prediction is enabled, requests to URLs are made without user consent. The browser should always make a direct DNS request without prefetching occurring.

Type "about:policies" in the browser window.

If "NetworkPrediction" is not displayed under Policy Name or the Policy Value is not "false", this is a finding.

Windows group policy: 1. Open the group policy editor tool with "gpedit.msc". 2. Navigate to Policy Path: Computer Configuration\Administrative Templates\Mozilla\Firefox Policy Name: Network Prediction Policy State: Disabled

macOS "plist" file: Add the following: <key>NetworkPrediction</key> <false/>

Linux "policies.json" file: Add the following in the policies section: "NetworkPrediction": false