This is an old revision of the document!
https://support.mozilla.org/en-US/kb/profile-manager-create-remove-switch-firefox-profiles
https://prism-break.org/en/projects/https-everywhere
https://prism-break.org/en/projects/ublock-origin
https://support.mozilla.org/en-US/products/firefox/sync-and-save
https://support.mozilla.org/en-US/kb/send-tab-firefox-desktop-other-devices
https://support.mozilla.org/en-US/products/firefox/protect-your-privacy
https://support.mozilla.org/en-US/kb/manage-passwords-firefox-desktop-firefox-lockwise