Privacy and security

Learn how to protect your privacy and secure your data.

Common Myths about Private Browsing

Learn more about common misconceptions about Private Browsing in Firefox.

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Third-party trackers

Learn about cross-site (third-party) cookies that collect information to track your browsing, which are used on many websites.

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Private Browsing on Firefox for Android

Private Browsing on your mobile device is great for viewing websites incognito - without saving information about the sites you visit.

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Configure DNS over HTTPS protection levels in Firefox

DNS over HTTPS (DoH) is a recommended feature that enhances privacy for everyone. When you type a web address into your address bar, Firefox sends a secure DNS request to look up the IP address for that website over the Internet and make sure it's secure. In this article, we explain all the DoH protection levels you can configure from the Firefox settings.

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Avoid and report Mozilla tech support scams

Mozilla does not provide telephone support and does not charge for software downloads, upgrades or technical help. Learn more.

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Choose a strong password

How to choose a strong password for your Mozilla account.

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Sponsored shortcuts on the New Tab page

Working with its advertising partners, Mozilla may place sponsored shortcuts on the default Firefox home page and New Tab page. Learn more.

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How do I set up Sync on my computer?

Use a Mozilla account to sync your bookmarks, history, passwords, add-ons and open tabs with another device, profile or version of Firefox.

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Global Privacy Control

How to make Firefox advise websites that you visit not to sell or share your browsing information.

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HTTPS-Only Mode in Firefox

Learn more about HTTPS-Only Mode which forces all connections to websites to use HTTPS.

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How do I turn on the Do Not Track feature?

Firefox lets you tell websites not to track your browsing behavior. Learn what tracking is and how to turn on the “Do Not Track” feature.

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Remote Content in Messages

This page explains the privacy implications of allowing remote content like images to be displayed in email messages.

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Pocket website cookies FAQ

Information about usage and customization of cookie settings on the Pocket website.

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Privacy-Preserving Attribution

Firefox 128 introduces privacy-preserving attribution, allowing advertisers to measure campaign performance while protecting user privacy.

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Troubleshoot Firefox issues caused by malware

Malware is software designed to invade a computer without your knowledge. We'll explain common symptoms, how to prevent it being installed and how to remove it.

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Automatically trust third-party root certificates

Root certificates are the backbone of the security system that underpins HTTPS web traffic. Firefox, like most web browsers, includes a pre-installed set of trusted root certificates.

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Telemetry collection and deletion

Firefox collects telemetry data by default and sends this data to Mozilla, to help improve Firefox performance and stability. Learn more.

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How to set up Firefox Sync in Firefox for Android

How to enable sync on Firefox for Android to sync your bookmarks, credit cards, history, logins and open tabs across your devices.

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How do I choose what information to sync on Firefox?

Learn how to select what information (bookmarks, add-ons, browsing history and other data) to share across your devices with Firefox Sync.

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Mixed content blocking in Firefox

Firefox automatically blocks insecure or mixed content from secure web pages. We'll explain what that means and what options you have.

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How to use Firefox containers

This article explains how to use Firefox containers with the Multi-Account Containers extension, to organize your online activities.

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Site Information panel

The Site Information panel in Firefox tells you about a website's connection security and identity. Learn more.

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I found a fake Firefox update

What to do if you spot fake notices claiming to contain an "urgent" or "critical" Firefox update.

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DNS over HTTPS (DoH) FAQs

We have outlined a list of FAQs here that you may find helpful while getting up to speed with all that DNS over HTTPS (DoH) has to offer.

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Resist Fingerprinting

Firefox's Advanced Preferences to resist fingerprinting can help prevent websites from uniquely identifying your device but can cause problems. Learn more.

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Firefox DNS over HTTPS

DoH improves privacy by hiding domain name lookups from anyone lurking on public Wi-Fi, your ISP or others on your local network. Learn more.

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Secure website certificate

Websites can present Firefox with a certificate to identify themselves. Find out how Firefox checks the authenticity of the sites you visit.

Firefox Firefox Last updated: 1 week, 1 day ago

Protect your container tabs with Mozilla VPN

Mozilla VPN encrypts your connection so that third parties can't track your online activity. Learn how to add this protection to Containers.

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How do I change my DNS settings?

This article will show you how to change your DNS settings on Mozilla VPN and why you might want to do that.

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Autofill logins on Firefox

Firefox lets you control whether or not to autofill your logins and passwords.

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Disable Firefox Sync

Learn how to turn off Firefox Sync if you’d like to use your Mozilla account without syncing data such as, bookmarks, history and tabs.

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OpenPGP in Thunderbird - HOWTO and FAQ

This article answers common questions about OpenPGP support in Thunderbird, as implemented in End-To-End Encryption (e2ee), and how it differs from Enigmail.

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Site Permissions panel

If you allow or block permissions for a website, the address bar will show a Permissions icon that opens the Permissions panel. Learn more.

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Change your Mozilla account password

How to change your Mozilla account password if you detect strange activity on your account.

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Thunderbird Telemetry

Thunderbird collects telemetry data by default. We collect this data to help improve the performance and stability of Thunderbird. Learn more.

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Firefox connection upgrades - HTTP to HTTPS

Firefox upgrades connections from HTTP to HTTPS to enhance security and protect your data. Learn about server- and browser-initiated upgrades and how they work.

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Is Mozilla VPN free?

Mozilla VPN is a paid subscription product that offers unlimited, comprehensive protection for up to 5 devices.

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Use Multi-Account Containers with Mozilla VPN

The Multi-Account Containers add-on separates your shopping, work, banking, Facebook and personal browsing activity. Learn how to integrate it with Mozilla VPN.

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Firefox Subprocessor List

Mozilla uses third-party subprocessors to help provide the Firefox desktop browser and related services. Learn what data is shared and more.

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How Firefox Sync keeps your data safe even if TLS fails

Firefox Sync encrypts your data before it ever leaves your device, and ensures that the password to unlock this encryption is never transmitted to the server.

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Mozilla VPN - FAQ

Find answers to some of the most common questions about Mozilla VPN in this article.

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HTTPS-First upgrades to secure connections

From version 136, Firefox implements HTTPS-First and always attempts to connect securely. If a secure connection fails it falls back to an insecure connection.

Firefox Firefox Last updated: 2 weeks, 5 days ago

How to stay safe on the web

There are many scams, viruses and other dangers out in the Web. Take these simple steps to protect your computer and personal information.

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How do I know the status of my sync?

The Mozilla account toolbar icon tells you when you are signed in and syncing Firefox data. You can personalize it with your own avatar.

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Disable password saving in Firefox

If you’re using a shared device and don’t want Firefox to remember your passwords, you can change your preferences in Firefox settings.

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Understand Encrypted Client Hello (ECH)

Firefox version 118 introduced a security enhancement called Encrypted Client Hello (ECH), enabled by default in Firefox 119. Learn more.

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Relay Phone Masking FAQ

Frequently asked questions about Relay Phone Masking.

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Disable Firefox Sync on a lost phone or tablet

This article describes what you should do to prevent someone from accessing your passwords on a lost device with Firefox Sync.

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Send usage data on Firefox mobile browsers

This article describes which data is collected by Firefox for Android, Firefox for iOS, Firefox Focus and Firefox Klar.

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Suspicious activity on my Mozilla account

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

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About Firefox Desktop Attribution

When you download and install Firefox, a "download token" is used, so Mozilla can identify how you reached the download page. Learn more.

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Usage Data Changes for Firefox for iOS and Android

Firefox began collecting new usage data to support the Firefox for iOS 39 and Android 94 releases to support personalization.

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Firefox Relay - Email and Phone masks

Learn what is an email mask, what is a phone mask, and how a mask can protect your real information on the internet and its benefits.

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What to do after a data breach

Learn what to do after Mozilla Monitor notifies you about a data breach, so that you can protect your accounts and limit any damage.

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Thunderbird and OpenPGP Alias Keys

How to use the OpenPGP Alias Keys feature to bypass Thunderbird's usual requirement that an OpenPGP public key must contain the recipient's email address.

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Data broker scan

Monitor Plus allows you to run a data broker scan to search if your information has been exposed. All premium users have an automated monthly scan.

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Monthly Monitor Report Email

The monthly Monitor Report email explains how Mozilla Monitor protects your information, without the need to sign in to Monitor. Learn more.

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Thunderbird Android Telemetry

This article describes controlling data that may be collected by Thunderbird for Android, to help improve performance and stability.

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Digitally Signing and Encrypting Messages

This tutorial explains how to set up Thunderbird to digitally sign, encrypt and decrypt messages in order to make them secure.

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Thunderbird and Logjam

Thunderbird no longer supports 512 bit (so called US export) keys for TLS connections.

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Private Browsing in Firefox Lite

Browse without saving history, cookies, passwords, site preferences or temporary Internet files. Learn more.

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Firefox Monitor

Firefox Monitor empowers users to fight against data breaches by alerting users when they visit a previously breached website.

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How do you use Adjust in Firefox?

How Adjust is used in Firefox mobile products.

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How do I reset Mozilla VPN?

This article explains how to clear Mozilla VPN app data from your device.

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Mask your phone number with Relay Phone Masking

Relay Phone Masking allows you to choose a phone number mask to protect your true phone number. In this article, you'll learn about the available features and steps to subscribe.

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Get started with Mozilla Monitor

Mozilla Monitor is a data breach notification service offered by Mozilla that warns you if your online accounts have been involved in a data leak.

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How do I change my Privacy features?

Learn how to activate and deactivate the Mozilla VPN Privacy features and how it can interact with your custom DNS settings.

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How does Monitor Plus work?

Learn how Monitor helps guard your personal information, from removing your details on data broker sites to assisting you post-data breach.

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Get started with Monitor Plus

Monitor Plus warns you when your online accounts have been compromised in a data breach, and automatically removes the exposures from the data broker sites.

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How to upgrade to Monitor Plus?

Learn how to upgrade to the premium feature Monitor Plus, and get a more robust protection with automatic removals from the data broker sites.

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Monitor status indicators

See the progression of data removal through different statuses designed to provide you a clear insight into the removal process that happens behind the scenes.

Mozilla Monitor Mozilla Monitor Last updated: 4 weeks ago

How Review Checker preserves user privacy

Learn how Review Checker uses OHTTP to securely send product info to Fakespot, ensuring no personal data or browsing details are shared.

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Securing a New Partner for Monitor Plus

Mozilla is working to secure a new vendor for Monitor Plus to maintain privacy standards while continuing services through OneRep temporarily.

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