• FirefoxHardening

This is a list of things I do when installing Firefox on a new machine.

First launch

Navigate to about:profiles and create a new profile with a sensible name. Delete the default profile.

Preferences

General

• Restore previous session: enabled
• Warn you when quitting the browser: enabled
• Ctrl+Tab cycles through tabs in recently used order: disabled
• Set a minimum font size
• Allow pages to choose their own fonts: disabled
• Set languages: fuckoff en-US; replace with actual English
• Do not open PDFs with Firefox
• Recommend extensions as you browse: disabled
• Recommend features as you browse: disabled

Home

• Web Search: disabled
• Sponsored Top Sites: disabled

Search

• Provide search suggestions: disabled
• Remove Amazon, Bing, eBay

Privacy and Security

• Enhanced Tracking Protection: Strict
• Do Not Track: Always
• Ask to save logins and passwords: disabled
• Permissions: disable everything
• Allow Firefox to send technical and interaction data to Mozilla: enabled... for now
• Allow Firefox to make personalised extension recommendations: disabled
• Allow Firefox to install and run studies: disabled
• Allow Firefox to send backlogged crash reports on your behalf: disabled
• Query OCSP responder servers: disabled
• Don't enable HTTPS-Only mode

about:config

See link:macos.asciidoc[macos notes] for _High-DPI_ workarounds.

• accessibility.force_disabled: 1

• beacon.enabled: false

• browser.send_pings: false

• browser.tabs.warnOnClose: false

• browser.urlbar.trimURLs: false

• dom.serviceWorkers.enabled: false

• extensions.pocket.enabled: false

• geo.enabled: false

• identity.fxaccounts.enabled: false

• network.IDN_show_punycode: true

• network.predictor.enabled: false

• network.prefetch-next: false

• ui.contextMenuOffsetHorizontal: 5 (must be created)

• ui.contextMenuOffsetVertical: 5 (must be created)

• webgl.disabled: true

If you do not intend to use WebRTC crap (Google Meet et. al.):

• media.navigator.enabled: false

• media.peerconnection.enabled: false

Extensions

Cookie AutoDelete

• Enable automatic cleaning: enabled
• Set 30s delay before automatic cleaning
• Enable cleanup on domain change: enabled
• Enable greylist cleanup on browser restart: enabled
• Enable IndexedDB cleanup: enabled

• Enable LocalStorage cleanup: enabled

• Enable Plugin Data cleanup: enabled
• Enable Service Workers cleanup: enabled
• Enable support for Container Tabs: enabled
• Show notification after automatic cleanup: disabled

Decentraleyes (defaults are fine)

uBlock Origin

• I am an advanced user: enabled
• Prevent WebRTC from leaking local IP addresses: enabled
• Enable all _Built-in_, _Ads_, _Privacy_, and _Annoyances_ filters. Enable _Dan Pollock's hosts file_ filter.

References

• http://sciops.net/information/technology/firefox

• https://chrisx.xyz/blog/yet-another-firefox-hardening-guide/