'''''bold text'''''how to up date firefox

Firefox since 79.0 and later has required Mac OS X 10.12 (ten.twelve) or later to run as you appear to have the old EOL Mac OS X 10.9. Firefox 78.15.0esr was the last to support the old EOL Mac OSX 10.9, 10.10, 10.11 https://support.mozilla.org/en-US/kb/firefox-mac-osx-users-esr You can download en-US locale of Firefox 78.15.0esr.dmg from https://archive.mozilla.org/pub/firefox/releases/78.15.0esr/mac/en-US/ other locales are at https://archive.mozilla.org/pub/firefox/releases/78.15.0esr/mac/ https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac