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Web browser for Windows, Mac and Linux
Firefox for Android
Web browser for Android smartphones and tablets
Firefox for iOS
Firefox for iPhone, iPad and iPod touch devices
VPN for Windows 10, Mac, Linux, Android, and iOS devices
Service that lets you create email masks to hide your real email address
Find out if your private information has been exposed in a known data breach.
Automatic privacy browser and content blocker
MDN Plus provides a custom user experience for MDN supporters.
Collaborate and engage with each other through spatialized audio and with media from around the web.
Firefox for Enterprise
Firefox Quantum for businesses
Email software for Windows, Mac and Linux
Firefox Private Network
Browse securely on public Wi-Fi using a Firefox add-on.
How to troubleshoot security error codes on secure websites
Learn about the error codes SEC_ERROR_UNKNOWN_ISSUER MOZILLA_PKIX_ERROR_MITM_DETECTED and ERROR_SELF_SIGNED_CERT on HTTPS websites and how to troubleshoot.
Firefox options, preferences and settings
Options/Preferences panels give you access to Firefox settings. This article describes what types of settings are available in each panel.
Enhanced Tracking Protection in Firefox for desktop
Enhanced Tracking Protection in Firefox automatically protects your privacy while you browse.
Secure connection failed and Firefox did not connect
If a website requires a secure connection that cannot be established, Firefox will not connect and will show you an error page. Learn more.
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