Privacy and security

Common Myths about Private Browsing

Learn more about common misconceptions about Private Browsing in Firefox.

Enhanced Tracking Protection in Firefox for desktop

Enhanced Tracking Protection in Firefox automatically protects your privacy while you browse.

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.

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.

Third-party trackers

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

Private Browsing in Firefox for iOS

Firefox lets you browse without saving your history or cookies on your iPhone or iPad.

Does Firefox share my location with websites?

Learn what information Firefox sends to websites about your location and how to use and manage location-aware features of your browser.

Choose a strong password

How to choose a strong password for your Mozilla account.

Automatically fill in credit card and payment method data on Web forms

Manage credit card autofill settings in Firefox version 81 and above.

Introducing Total Cookie Protection in Standard Mode

Firefox users now have access to Total Cookie Protection by default. Find all you need to know about it in this article.

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.

Insecure connection password warning in Firefox

Firefox will show you a "connection is not secure" warning message when a website login page is insecure and information could be stolen.

HTTPS-Only Mode in Firefox

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

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.

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.

Pop-up blocker settings, exceptions and troubleshooting

Learn what pop-up windows are and what settings Firefox has for blocking or allowing them.

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.

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.

Protect privacy while using Web Authentication

Learn about Web Authentication, a powerful anti-phishing technology.

Enhanced Tracking Protection in Firefox for Android

Control who's watching you on the Internet. This article explains how to turn on Tracking Protection in Firefox for Android.

Trackers and scripts Firefox blocks in Enhanced Tracking Protection

Blocks many common trackers and harmful scripts and reduces the ability of third parties to collect data about your browsing behavior

HTTPS-Only Mode in Firefox for Android

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

How does built-in Phishing and Malware Protection work?

Firefox contains built-in Phishing and Malware Protection to help keep you safe online. This article explains how they work.

Use a Primary Password to protect stored logins and passwords

Setting a Primary (formerly "Master") password in Firefox is helpful if your share your computer with others. We'll explain how it works.

Mozilla Monitor - Frequently asked questions

Frequently-asked questions for Mozilla Monitor.

How to manage your camera and microphone permissions with Firefox

How to enable or block sites from accessing your camera and microphone on your desktop or mobile device.

Why are some add-ons not allowed on sites restricted by Mozilla?

Learn why some Firefox add-ons might not work on certain websites and how to manage those extensions to enhance your browsing experience.

Global Privacy Control

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

Secure your Mozilla account with two-step authentication

Protect your Mozilla account with two-step authentication.

Delete browsing, search and download history on Firefox

Learn what information is stored in your Firefox history and how to clear all or part of it if you are using a public or shared computer.

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.

Remote Content in Messages

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

SmartBlock for Enhanced Tracking Protection

SmartBlock lets pages load more fully, with less breakage — all while keeping those tracking scripts blocked.

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.

Password Manager - Remember, delete and change passwords in Thunderbird

The Thunderbird Password Manager securely stores your username and passwords. Learn how to save, view, delete and edit your passwords.

Microsoft OAuth Authentication and Thunderbird in 2024

Changes to OAuth authentication for Microsoft 365 (formerly Office 365; often abbreviated as “o365”) business and academic hosted email accounts and services.

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.

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.

Introduction to End-to-end encryption in Thunderbird

This article explains what end-to-end encryption is and how to use it to protect the contents of your email in Thunderbird.

Enhanced Tracking Protection in Firefox for iOS

Firefox for iOS has a Tracking Protection feature which reduces targeted ads and helps stop advertisers from tracking your browsing.

Mozilla account - Managing account data

How to manage your Mozilla account data.

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.

How to use Firefox containers

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

Create secure passwords to keep your identity safe

Choosing more secure passwords will help keep your identity safe on the internet. Learn how to create secure, easy-to-remember passwords.

Private Browsing - Use Firefox without saving history

Firefox Private Browsing is great for viewing websites without saving things such as cookies, temp files and a history of the pages you visit.

How do I tell if my connection to a website is secure?

Firefox uses a padlock icon next to a website's URL to let you know your connection is encrypted. Click on the icon for more information.

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.

Search suggestions in Firefox

Learn more about how search suggestions work in Firefox.

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.

Site Information panel

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

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.

Why do I get a harmful download message when downloading Firefox on Windows?

You may see a warning that the installer could harm your device when attempting to download Firefox from another browser. Learn more.

Resist Fingerprinting

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

Set up a passcode and Face ID in Firefox for iOS

For increased security, you can choose to activate either Face ID, Touch ID, or a passcode to access your stored passwords.

My sign in was “blocked for security reasons” on Mozilla account

Mozilla account blocks sign in attempts if it detects unusual activity. Learn how to unblock your account.

Browsing history in Firefox - View the websites you have visited

Firefox keeps track of the websites you visit when you browse the Web. Learn how to view, search and sort your browsing history.

How to generate a secure password in Firefox

Learn how Firefox can create a secure password for you when creating a new online account.

Secure Firefox passwords with device sign-in

Learn more about this Firefox anti-snooping feature designed to protect your logins and passwords from unauthorized access.

Clear your browsing history and other personal data on Firefox for Android

Firefox for Android makes it easy for you to delete your browsing information. You can even automatically delete your data every time you quit Firefox.

Share data with Mozilla to help improve Firefox

The Telemetry feature sends us performance and usage data to help measure how Firefox behaves in the real world and improve it. Learn more.

Remove a synced device from your Mozilla account

Disconnect a device from your Mozilla account and stop syncing its data.

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.

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.

Autofill logins on Firefox

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

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.

Thunderbird Android Telemetry

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

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.

Clear your browsing history in Firefox for Android

Firefox keeps a record of your browsing history. Learn how you can remove items from your history one-by-one, or clear your history entirely.

Clear browsing history in Firefox for iOS

Clear your browsing information, like sites you've visited, autofill information and site preferences.

Sync bookmarks, logins and browsing history on Firefox for iOS

Pair Firefox for iOS with Firefox desktop and Android to sync your bookmarks, logins and other browsing information across devices.

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.

How Firefox securely saves passwords

Learn how Firefox securely saves your passwords.

Manage your logins with the Firefox Password Manager

Manage your saved logins and passwords on desktop Firefox with the built-in password management feature.

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.

Turn on/off saved logins, login sync and login autofill in Firefox for Android

Learn how to save, sync and access your logins in Firefox for Android

Thunderbird Telemetry

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

Delete sync data from Firefox by signing out of your Mozilla account

How to sign out of your Mozilla account and remove your synced data from a device.

Clear cookies and website data for a single domain in Firefox for Android

You can delete your cookies and website data for a single domain in Firefox for Android, without losing your logins for other domains.

Firefox privacy and security features

Check Firefox's most advanced features and settings for safe, private online browsing.

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.

Instructions for obtaining a personal S/MIME certificate by creating a CSR

Description of the manual process of obtaining an S/MIME certificate for email security, using a Certificate Signing Request (CSR) generated by Thunderbird.

How to stop Firefox from making automatic connections

Learn about the various reasons why Firefox makes automatic connections to the Internet and how you can stop it from doing so if you wish.

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.

Total Cookie Protection and website breakage FAQ

Learn about Enhanced Tracking Protection and Total Cookie Protection in Firefox, and how to troubleshoot and report possible site breakage.

Automatic Conversion of Google mail accounts to OAuth 2.0 Authentication

Thunderbird 91.8.0, released 5th April 2022, converts Gmail accounts to OAuth 2.0 in compliance with Google's schedule for requiring this login method.

Encrypted Client Hello (ECH) - Frequently asked questions

Encrypted Client Hello (ECH) is a security feature in major Web browsers, available in Firefox 118 and enabled by default in Firefox 119. Learn more.

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.

How do I share Firefox between people on a computer?

Firefox can be used by several people on a single computer. Learn the basic protections to prevent others form accessing your private data.

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.

Change your Mozilla account password

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

Suspicious activity on my Mozilla account

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

Keep Private Browsing tabs open after exiting Firefox

Adjust Firefox settings to retain Private Tabs when exiting the app.

Changing your two-step authentication device for your Mozilla account

What to do if you have two-factor authentication (2FA) setup on your account and need to migrate to a new device or phone.

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.

Primary Password is replacing Master Password

Primary Password is replacing Master Password. Learn more about why we are making this change.

OpenPGP Recipient Alias Configuration

How to set up and use the OpenPGP recipient Alias feature in Thunderbird.

How do I reset Mozilla VPN?

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

How does Firefox for iOS use the permissions it requests?

When using specific functions in Firefox, iOS asks you to grant a number of permissions. This article explains what these permissions mean and how they are used.

How do I monitor multiple email addresses?

This article will show you how to add or exclude email addresses on Mozilla Monitor.

Firefox accounts renamed Mozilla accounts - What you need to know

Firefox accounts has been renamed Mozilla accounts since it's now used by various products and services to authenticate and manage accounts.

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.

Global Privacy Control in Firefox for Android

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

Generate strong passwords in Firefox for Android

Learn how to use the built-in password generator in Firefox on Android to create strong, secure passwords automatically.

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.

How do I enable the Firefox OS phone lock?

Firefox OS phones have a feature that locks the phone automatically when idle. Learn how to turn it on.

Protect your Thunderbird passwords with a Primary Password

Make Thunderbird require you to enter a primary password in order to view or use passwords you've told Thunderbird to remember.

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Certificates

Why does Thunderbird warn me that my server don't use encryption?

How Thunderbird’s scam detection works?

How can I digitally sign and encrypt emails?

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.

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.

Firefox Monitor

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

How do you use Adjust in Firefox?

How Adjust is used in Firefox mobile products.

Tracking Protection in Firefox Preview

Learn about Tracking Protection and how to turn it off.

"Certificate cannot be trusted" warning in Kazakhstan

Firefox is blocking the use of Kazakhstan root CA certificate to protect your privacy. Learn more about how to stay safe.

My privacy settings were changed from Custom to Standard

If your Custom settings match the settings in Standard, you will be switched back to Standard. This will not affect your settings.

Telemetry collection - Windows default browser trends

This article explains one example of how Firefox collects and uses telemetry data with the Default Browser Agent Windows scheduled task.

Activate Firefox Relay - Mask your email address

Relay is a Firefox extension that keeps your real email address from companies you don’t trust.

Create an email mask through Firefox Relay

How to create an email mask on Relay.

Disable email forwarding - Stop receiving emails sent through your masks

You can permanently delete a mask or temporarily disable forwarding to stop receiving emails in your inbox.

Grant camera access to Firefox for Android

How to grant camera access so Firefox can scan a QR code.

Use Web Apps with Firefox for Android

Learn more about Web apps and how to use them with Firefox for Android.

Primary Password is replacing Master Password in Thunderbird

Primary Password is replacing Master Password. Learn more about why we are making this change.

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.

Install the Firefox Relay extension on Firefox for desktop

Extensions customize and add functionalities to Firefox. Add the Firefox Relay extension to generate a mask when you register on websites.

Unsafe properties of OpenPGP keys might be ignored

If Thunderbird unexpectedly reports that an OpenPGP key is expired, or isn't showing some expected properties, the key might have unsafe properties.

Search your browsing history in Firefox for iOS

You can search your browsing history within the History panel in Firefox for iOS.

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.

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.

Disable credit card and payment method syncing across devices

Disable credit cards and payment method syncing to prevent unwanted purchases on your shared devices.

Block deceptive content and dangerous downloads in Firefox

Make sure these settings are enabled to prevent unwanted downloads and block suspicious content on your children's sessions.

Resolve breaches with Mozilla Monitor

This article explains how you can resolve data breaches in online accounts by using Mozilla Monitor.

Unlink your Google or Apple ID from your Mozilla account

If you no longer want to use your Google or Apple account to sign in to your Mozilla account, you can unlink it in your Mozilla account settings.

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.

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.

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).