Firefox Download [hot] For Mac 10105 Upd May 2026

For macOS 10.10.5 (Yosemite), the final compatible version of Firefox is Firefox 78.15.0esr. Because modern versions of Firefox require macOS 10.15 or later, you must manually download this specific "Extended Support Release" (ESR) version from Mozilla’s archives. Guide to Downloading Firefox for Mac 10.10.5

Download the Correct Version:Access the official Mozilla archive to download the compatible installer directly: Download Firefox 78.15.0esr (English US).

If you need a different language, navigate the Mozilla FTP directory to find your specific locale folder. Installation Steps:

Locate the downloaded .dmg file in your Downloads folder and double-click it.

A window will appear; drag the Firefox icon into your Applications folder. firefox download for mac 10105 upd

Open Firefox from your Applications folder. You may see a security warning since it is an older version; click Open to proceed.

Disable Automatic Updates:To prevent Firefox from trying to update to an incompatible version, you should immediately disable automatic updates:

Click the Firefox menu (three horizontal lines) and select Settings.

In the General panel, scroll to the Firefox Updates section. For macOS 10

Select Check for updates but let you choose to install them and uncheck Use a background service to install updates. Important Considerations

Security Risks: Firefox 78 ESR stopped receiving security updates in October 2021. Using it for sensitive activities like online banking is not recommended as it lacks modern protection against newer threats.

Website Compatibility: Some modern websites may not load correctly or may display formatting issues because this version of Firefox does not support the latest web standards.

Better Alternatives: If your hardware supports it, consider upgrading your OS to macOS 10.11 (El Capitan) or 10.13 (High Sierra) to use slightly newer (though still aging) browsers like Firefox 115 ESR. Latest Firefox versions (90+) do not support macOS 10

1. Compatibility Overview

| Firefox Version | macOS 10.10.5 | Security Updates | |----------------|---------------|------------------| | Firefox 78 ESR | ✅ Yes | ❌ No (EOL) | | Firefox 79+ | ❌ No | N/A |

Step-by-Step: Firefox Download for Mac 10105 (Yosemite)

Follow these instructions carefully. Do not use the main green download button on Mozilla’s homepage—that is for modern macOS versions.

The Security Warning

If you are stuck on OS X 10.10.5, you need to be aware of the risks: