Firefox: the settings worth your attention

Start with the sites you use

Your bank, videos and email need to keep working after a setting changes. Keep those sites handy while configuring Firefox. You will quickly see whether a protection blocks a feature you need.

This guide mainly covers desktop Firefox: permissions, extensions, storage and tracking protection. Mobile options differ. Start from your current settings and change one thing at a time so you can undo it if needed.

Start with Standard; try Strict against your actual needs

Enhanced Tracking Protection is already enabled. Standard mode includes Total Cookie Protection, which partitions cookie storage by site. Strict mode blocks more tracking content and can disrupt some pages.

Choose five representative services before changing modes. Then try a sign-in, a form, a video and a shopping basket without making a purchase. If something fails, Firefox’s shield lets you inspect that site’s protections and create a local exception. Record why you needed it; exceptions should not become your automatic response to every problem.

Review extensions and permissions

Installing an extension is a decision about trust. Its value should justify its permissions. An extension that changes every page may need broad access. An extension you have forgotten keeps that access without providing the same benefit.

1. Install Firefox from its official website and check that updates work. Keep your previous browser until you have confirmed access to your accounts.
2. Open the extension list. Describe what each one does for you. Check the origin of anything unfamiliar, then remove duplicates and tools you no longer need.
3. Review notification, location, camera and microphone permissions. Access granted for a one-off meeting may no longer need to be permanent.
4. Try your everyday services after each individual change. Keep a short note of the setting, the result and how to reverse it.

Two accounts on one website: containers

Mozilla’s Multi-Account Containers extension separates cookie contexts. You can open a personal account in one container and another account in a second, without signing out of the first. You can also assign a site to a particular container.

Containers keep different accounts’ sessions separate. The network and device remain the same, however; containers do not guarantee that sites will never be able to link those activities. Start with two clearly named containers to learn how links open between them.

HTTPS and encrypted DNS protect different things

HTTPS-Only Mode tries to establish an encrypted connection and warns when it cannot. It protects transport; a fraudulent website can also use HTTPS. A padlock does not endorse the content behind it.

DNS over HTTPS encrypts resolution requests to a resolver. You still need to trust that recipient, and it does not hide all traffic. On a managed network, check the consequences before forcing a provider: local names, intentional filtering and network policies can be affected.

A private window does not erase your network presence

Private Browsing mainly limits what Firefox retains when the private session ends. It does not make you invisible to your internet provider, employer or websites. Downloads and bookmarks you create remain on the device.

It can suit a one-off visit without keeping that session in your regular profile. It cannot by itself protect sensitive activity on a computer someone else administers. Keep asking whose observation you want to reduce, and on which part of the journey.

• What your browser reveals before the first click↗

Maintain your setup

Once you have checked your usual sites, note the exceptions and extensions you kept. That gives you a reference if a problem appears after an update.

A separate profile can hold a distinct activity, with its own extensions and accounts. Revoke permissions for sites you no longer use, too. Revisit these choices when your habits change, and avoid adding settings you would not know how to undo.