Privacy and security

Learn how to protect your privacy and secure your data.

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.

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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.

Firefox Firefox Last updated: 3 weeks, 1 day ago

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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HTTPS-Only Mode in Firefox

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

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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 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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Privacy-Preserving Attribution

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

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Global Privacy Control

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

Firefox Firefox Last updated: 3 weeks, 6 days ago

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.

Firefox Firefox Last updated: 3 weeks, 5 days ago

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 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 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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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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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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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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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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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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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 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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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.

Firefox Firefox Last updated: 4 weeks ago

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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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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Change your Mozilla account password

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

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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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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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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.

Firefox Firefox Last updated: 4 weeks ago

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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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 Firefox Last updated: 1 week, 6 days ago

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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