Performance and connectivity

Deal with error messages, crashing applications, connectivity issues, and slow performance.

Connection settings in Firefox

Your organization or Internet Service Provider may offer or require you to use a proxy to connect to the Internet. Learn more.

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What do the security warning codes mean?

Firefox shows you a warning page about a potential security risk when you try to connect to a secure site but your connection is not secure.

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Manage the devices linked to your Mozilla account

Find solutions to help you manage the devices and services connected to 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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Resist Fingerprinting

Resist Fingerprinting in Firefox limits the personal characteristics of the operating system and hardware exposed to websites

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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 to obtain the Mozilla VPN Logs

When troubleshooting issues with Mozilla VPN, our engineers can ask for logs. These don't contain any personal information, but give hints about the issue.

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Firefox for iOS won't load web pages

If a website isn’t loading even after you’ve checked the Internet connection, here are a few things you can try.

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RCS messaging and Mozilla VPN

RCS (Rich Communication Services) messaging on iOS 18 does not work when using Mozilla VPN. Learn how to fix or work around this issue.

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