Firefox Esr 78 Fix May 2026

Immediately inventory all endpoints running Firefox 78.x, isolate any that cannot be upgraded, and enforce a migration to Firefox ESR 128 or a modern Chromium-based alternative. Appendix: Check script for Linux endpoints

#!/bin/bash if firefox --version | grep -q "78\.\|78\.0\|78\.1"; then echo "CRITICAL: Firefox ESR 78 detected. Upgrade required." exit 1 fi firefox esr 78

Date: April 13, 2026 Subject: End-of-Life (EOL) Software Review Audience: System Administrators, Security Compliance Officers, DevOps Engineers 1. Introduction Firefox Extended Support Release (ESR) 78 was a major version of Mozilla’s browser, released on June 30, 2020 . It served as the foundational browser for thousands of enterprises, educational institutions, and public sector organizations until its official End-of-Life (EOL) on November 1, 2021 (with the final point release, 78.15.0, ending support). Immediately inventory all endpoints running Firefox 78