# Backup old profile cp -r ~/.mozilla/firefox/xxxx.esr78 ~/backup/
Firefox ESR 78: A Comprehensive Guide to Enterprise Stability
Firefox ESR 78 was a stable, performant browser for its time, effectively bridging the gap between legacy web standards (Flash, TLS 1.0 removal) and modern security. However, as of 2026, it is . firefox esr 78
The Firefox ESR 78 branch was supported for over a year, with its final release (78.15.0) occurring on October 5, 2021. It was replaced by the Firefox ESR 91 branch. Following the final release, support for 78.x ceased, and administrators were advised to migrate to the new branch to continue receiving security updates. Firefoxhttps://www.firefox.com
A "Refresh" button was added to the uninstaller, making it easier to resolve browser issues without complete reinstallation. Enterprise Deployment and Customization # Backup old profile cp -r ~/
Enhanced deployment options allowed administrators to run Firefox in a dedicated, full-screen mode, ideal for public-facing terminals.
: For the first time in the ESR channel, Service Workers and the Push API were enabled by default, supporting more modern web applications and offline functionality. It was replaced by the Firefox ESR 91 branch
Firefox ESR 78 marked a significant step in Mozilla’s "Quantum Render" project. WebRender moves the rendering of web pages from the CPU to the GPU (Graphics Processing Unit).