At least Mozilla documents every connection made and explains why they're made, and how to disable them: https://support.mozilla.org/en-US/kb/how-stop-firefox-

At least Mozilla documents every connection made and explains why they're made, and how to disable them: https://support.mozilla.org/en-US/kb/how-stop-firefox-making-automatic-connections https://support.mozilla.org/en-US/kb/how-stop-firefox-making...