Esr 78: Firefox

Firefox ESR 78 brought updated minimum system requirements. Notably, it was the final major release to support older macOS versions, specifically macOS 10.9, 10.10, and 10.11.

New policy specifically for Windows to prevent the default browser agent from prompting users. System Requirements and Compatibility firefox esr 78

Firefox ESR 78 leaves distinct traces that differ from newer versions: Firefox ESR 78 brought updated minimum system requirements

Using Firefox 78.15 or earlier on a network connected to the internet in 2026 exposes the system to over 150 known, unpatched CVEs. specifically macOS 10.9

Firefox ESR 78 brought updated minimum system requirements. Notably, it was the final major release to support older macOS versions, specifically macOS 10.9, 10.10, and 10.11.

New policy specifically for Windows to prevent the default browser agent from prompting users. System Requirements and Compatibility

Firefox ESR 78 leaves distinct traces that differ from newer versions:

Using Firefox 78.15 or earlier on a network connected to the internet in 2026 exposes the system to over 150 known, unpatched CVEs.