Step one: How do you completely turn off update checks in Firefox v64? You can use a policies.json file to disable updates for all users. https://github.com/mozilla/policy-templates/blob/master/README.md or https://winaero.com/blog/disable-updates-firefox-63-above/ You can use a policies.json file in the distribution folder in the Firefox installation folder instead as also listed in the article, so no need to use GPO keys in the Windows Registry. • https://support.mozilla.org/en-US/kb/customizing-firefox-using-policiesjson ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ You can use the ManualAppUpdateOnly policy in Firefox 87+ to enable only manual updates e.g. via "Help -> About Firefox". * https://github.com/mozilla/policy-templates#manualappupdateonly * https://support.mozilla.org/en-US/kb/customizing-firefox-using-policiesjson Note that it is important to stay up to date and install the latest security patches. * https://www.mozilla.org/security/known-vulnerabilities/firefox.html

Note that Firefox 78.15.0 is the last version for your Mac OS X platform (mozilla-mac-eol-esr1), so you will no longer receive updates. *https://support.mozilla.org/en-US/kb/firefox-mac-osx-users-esr