Mozilla: New Firefox extensions must disclose data collection practices

Mozilla is introducing a requirement for Firefox extension developers to declare whether their add-ons collect or share user data via a new browser_specific_settings.gecko.data_collection_permissions key in manifest.json starting November 3, 2025, with full adoption expected in the first half of 2026. Declarations must state any personally identifiable information collected (or explicitly state none), will be shown at install and on addon pages, and failure to declare will block submissions; the change applies to new extensions immediately and to existing add-ons when they adopt the new framework.