Privacy and security

Use built-in VPN in Firefox

Learn how to activate and use the built-in VPN feature in Firefox to protect your browsing.

Last updated: 1 week ago

Troubleshoot network errors when TLS key logging is enabled

Learn why Firefox shows a TLS key logging warning and how antivirus or security software may affect secure connections.

Created: 6/25/26

Firefox Password Manager - Alerts for breached websites

Firefox's password management will show you alerts about logins potentially exposed in data breaches and passwords that may be vulnerable.

Last updated: 6/5/26

Control personal device and local network permissions in Firefox

Learn why Firefox now asks permission before allowing sites to access your personal device or local network.

Last updated: 7/22/26

Firefox security features warning on Linux

Create an AppArmor profile for Firefox on Linux.

Last updated: 3/5/25

Unable to find the built-in VPN in Firefox

Some useful pointers if you are unable to access the built-in VPN in Firefox.

Last updated: 7/16/26

Use breach alerts in Firefox

Learn how Firefox warns you about website data breaches and helps protect your accounts and passwords.

Last updated: 7/6/26

Recommended Firefox privacy and security settings for families

Firefox lets you customize privacy and security settings so you and your family can browse safely online. Learn more.

Last updated: 6/15/26

Certificate contains the same serial number as another certificate

Why Firefox may show you a Secure Connection Failed error when you try to access the configuration page for your router and what to do.

Last updated: 6/16/26

Block and unblock websites with parental controls on Firefox

This article explains how to block websites or filter website content in Firefox that may be offensive or inappropriate for children.

Last updated: 8/11/22

Sign in to a Mozilla account using 3rd-party authentication

You can use your existing Google or Apple ID to sign up for a Mozilla account. Learn more.

Last updated: 3 weeks ago

Suspicious activity on my Mozilla account

How to protect yourself if suspicious activity is detected on your Mozilla account.

Last updated: 2 weeks ago

Compatibility with Exploit protection on Windows

Firefox Compatibility with Windows Exploit protection.

Last updated: 6/29/22

Data Loss Prevention

Seeing the DLP icon in Firefox? Here’s what it means and how it helps protect your data.

Last updated: 11/5/24

Understand unexpected script warnings in Firefox

Learn what unexpected script warnings in Firefox mean, why they happen, and what you should do if you see one.

Last updated: 8/20/25

Harmful add-on protection

If you have installed an add-on that triggers the opening of a known malicious website, Firefox will block it to protect you.

Last updated: 2/12/26

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