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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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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Third-party trackers

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

Firefox Firefox Last updated: 4 weeks, 1 day ago

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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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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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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Choose a strong password

How to choose a strong password for your Mozilla account.

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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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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 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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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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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.

Firefox Firefox Last updated: 2 weeks, 3 days ago

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 for Android

HTTPS-Only Mode is available for Firefox for Android. You can turn this setting on or off.

Firefox for Android Firefox for Android Last updated: 3 weeks, 6 days ago

Allow or block media autoplay in Firefox

Firefox prevents media from playing automatically on websites you visit, unless you grant permission. Learn more about this feature.

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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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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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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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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.

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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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What if I'm locked out of Two-Step Authentication?

Disable two-step authentication or use a backup authentication code to regain access to your account if you've been locked out of two-step authentication login.

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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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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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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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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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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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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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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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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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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.

Firefox Focus, Firefox for Amazon Devices,... Firefox Focus, Firefox for Amazon Devices, Firefox for Android, Firefox for Android Beta, Firefox for Fire TV, Firefox for iOS, Firefox Klar, Firefox Lite, Firefox Reality Last updated: 1 week ago

Thunderbird Android Telemetry

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

Thunderbird for Android Thunderbird for Android Last updated: 1 week, 3 days ago

Customize Firefox Home on iOS

Firefox Home on your iOS device displays your shortcuts, your library, recently visited tabs, recently saved bookmarks and Pocket article recommendations.

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Using a Primary Password with Sync

Learn how to use Sync in Firefox with a Primary Password (formerly known as a “Master Password”) for extra protection.

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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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How do I reset Mozilla VPN?

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

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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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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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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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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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Change your Mozilla account password

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

Firefox, Mozilla Account Firefox, Mozilla Account Last updated: 1 week, 3 days ago

Suspicious activity on my Mozilla account

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

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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.

Firefox Focus, Firefox for Android, Firefox... Firefox Focus, Firefox for Android, Firefox for iOS, Privacy and Security Last updated: 1 week, 3 days ago

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.

Firefox for Android, Firefox for iOS Firefox for Android, Firefox for iOS Created:

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.

Mozilla Monitor Mozilla Monitor Last updated: 4 weeks, 1 day ago

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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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.

Mozilla Monitor Mozilla Monitor Last updated: 6 days, 18 hours ago

Resist Fingerprinting

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

Firefox Firefox Last updated: 3 days ago

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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OpenPGP in Thunderbird for Android - How To

How to set up OpenPGP support in Thunderbird for Android, as implemented in End-To-End Encryption (e2ee).

Thunderbird for Android Thunderbird for Android Created: 5 days, 1 hour ago
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