ESR stands for Extended Support Release. This is a version of Firefox intended for schools, universities, and businesses that need a stable browser for longer periods. While standard Firefox updates every few weeks with new features, ESR updates less frequently and focuses strictly on security patches.
Since this is an older build, macOS might block it due to an expired gatekeeper ticket. If you see the warning “Firefox can’t be opened because it was not downloaded from the App Store”:
As of late 2024, Mozilla Firefox has ended support for Mac OS X 10.10 (Yosemite).
If you try to download the standard installer from the main Mozilla homepage, you will likely receive a message that your operating system is incompatible.
The last supported version for OS X 10.10.5 is Firefox 78.15.0 ESR.
⚠️ Recommendation: If possible, upgrade macOS or use a lightweight modern browser like Chromium Legacy or Waterfox Classic.
| Firefox Version | macOS 10.10.5 | Security Updates | |----------------|---------------|------------------| | Firefox 78 ESR | ✅ Yes | ❌ No (EOL) | | Firefox 79+ | ❌ No | N/A |
If your Mac hardware supports it, the best "update" isn't a new browser—it’s a new OS.
Summary: If you cannot upgrade your OS, Firefox 78.15.0 ESR is your stopgap. However, for your own cybersecurity, it is highly recommended to look into upgrading your macOS version or considering a hardware upgrade soon.
Running Firefox on Mac OS X 10.10.5 (Yosemite) If you are using a classic Mac running OS X 10.10.5 (Yosemite)
, you may have noticed that downloading the "latest" version of Firefox from the main Mozilla website
doesn't work. This is because modern versions of Firefox (v116 and later) require at least macOS 10.15 (Catalina)
However, you can still get Firefox running by using a specific older version. Here is what you need to know to get back online safely. The Best Version for Yosemite: Firefox 78 ESR
The absolute latest official version of Firefox that supports OS X 10.10.5 is Firefox 78.15.0 Extended Support Release (ESR)
The Extended Support Release channel was designed to provide long-term support for older systems. While it is no longer receiving new security patches as of October 2021
, it remains the most functional official version for your OS. Where to Download: You can find older versions in the Mozilla release archives or through reputable community repositories like the Macintosh Repository How to Install Download the DMG: Locate the installer for Firefox 78.15.0esr. Open the File: Double-click the downloaded Drag to Applications: Drag the Firefox icon into your Applications Confirm the Version: Open Firefox, go to the top menu, and select Firefox > About Firefox to ensure you are on version 78. Critical Security Warning
Because Firefox 78 ESR stopped receiving security updates in late 2021, it is vulnerable to modern web exploits. For a more secure experience on Yosemite, consider these alternatives: How to update outdated browser on OS X Yosemite 3 Sept 2024 —
For macOS 10.10.5 (Yosemite), the final supported version of Firefox is Firefox 78 ESR. You can still find this legacy installer through official Mozilla Support channels or verified archives like Macintosh Repository. The Ghost in the Machine: A Yosemite Elegy
There is a particular kind of stubbornness required to maintain a Mac running OS X 10.10.5 Yosemite. In the fast-paced timeline of Silicon Valley, a decade-old operating system is effectively a fossil. Yet, for those of us still clutching our 2012 MacBooks, Yosemite isn't just software; it's a preserved ecosystem, a digital time capsule of flat icons and translucent sidebars that marked the transition into Apple's modern aesthetic. firefox download for mac 10105 upd
The challenge of living in this past is the narrowing window to the present: the web browser. As security protocols evolve, the modern web slowly "blinds" older machines. This is where Firefox 78 ESR (Extended Support Release) enters the story as a loyal companion. It was the final version to keep the lights on for Yosemite before the support bridge was officially dismantled in October 2021.
Downloading Firefox 78 for an aging Mac is an act of digital preservation. It allows an old friend to continue "buying cat food and banking," as one archivist poignantly put it. It is the difference between a functional tool and a beautiful aluminum brick. We keep these machines not because we can't afford the new, but because the old still works, its keys worn smooth by years of shared history. In a world of planned obsolescence, choosing to find that one compatible installer is a small, quiet rebellion—a way of saying that even in the digital age, some things are worth keeping around.
How to Download Firefox for Mac OS X 10.10.5 (Yosemite) If you’re still using a classic Mac running OS X 10.10.5 Yosemite
, you may have noticed that many modern browsers no longer support your operating system. However, you can still get a functional and relatively secure version of Firefox to keep your machine surfing the web. The Last Compatible Version: Firefox 78 ESR
For users on Mac OS X 10.10.5, the most up-to-date official version available is Firefox 78 Extended Support Release (ESR)
. This was the final major release to support Yosemite before Mozilla moved its minimum requirements to macOS 10.12 Sierra and later. Firefox 78.15.0esr
This version is no longer receiving security updates as of October 2021. Why use it?
It is generally more compatible with modern websites than the outdated version of Safari that comes with Yosemite. Step-by-Step: How to Download and Install Since the main Firefox Download Page
will automatically try to give you the newest version (which won't open on 10.10.5), you need to follow these steps: Locate the Correct Installer : You can find older versions on the Mozilla CDN server or through reputable archives like Download the DMG : Save the Firefox 78.15.0esr.dmg file to your Downloads folder. : Open the DMG file and drag the Firefox icon into your Applications folder
: Open your Applications folder and double-click Firefox. If you see a warning about an app "downloaded from the internet," click Important Tips for Legacy Users Security Risks
: Because Firefox 78 ESR has not had security patches in years, avoid using it for sensitive tasks like online banking. Website Issues : If a site looks "broken," it might be due to Enhanced Tracking Protection . Click the shield icon
in the address bar to try disabling it for that specific site. Upgrade Options : If your hardware allows it, consider upgrading your OS to 10.11 El Capitan 10.13 High Sierra . High Sierra supports Firefox 115 ESR
, which remained supported with security updates much longer.
For users on Mac OS X 10.10.5 (Yosemite) , the journey to a modern browsing experience has a specific finish line. Since 2021, Mozilla has officially ended support for this operating system version, but there is still a way to get a compatible version running. Apple Support Community The Recommended Version: Firefox 78 ESR
The latest and final version of Firefox that works on Mac OS X 10.10.5 is Firefox 78 Extended Support Release (ESR) Mozilla Support Current Status
: This version is no longer receiving security updates as of October 2021. Functionality
: While it can still browse many websites, some modern features or highly secure sites may encounter compatibility issues. Apple Support Community How to Download and Install
Since the main Firefox download page will typically offer the newest version (which requires macOS 10.15 or later), you must use the official archive for the older version. Mozilla Support Download the Installer : Access the Official Mozilla Archive for 78.15.0esr to download the Open the DMG ESR stands for Extended Support Release
: Double-click the downloaded file to open the installer window. : Drag the Firefox icon Applications folder
: Open Firefox from your Applications folder. You may need to click "Open" on a security prompt since it is an older software package. Mozilla Support Why You Can't Get Newer Updates
Mozilla moved users on OS X 10.9, 10.10, and 10.11 to the Extended Support Release (ESR) channel to provide a few extra years of security. However, maintaining support for decade-old operating systems became unsustainable as web technologies evolved. Mozilla Support Better Alternatives for Your Mac
If your hardware allows it, experts recommend upgrading your macOS to at least 10.15 Catalina
or higher to use the latest, most secure version of Firefox.
Download Firefox for Mac OS X 10.10.5 (Yosemite)
If you're using Mac OS X version 10.10.5 (Yosemite), you can still run an older but stable version of Firefox that is compatible with your system.
Important Note:
The latest versions of Firefox no longer support OS X 10.10.5. The last compatible release is Firefox 78 ESR (Extended Support Release), which includes security updates until November 2021.
Steps to Download Firefox 78 ESR for OS X 10.10.5:
Direct download link (official Mozilla source):
https://ftp.mozilla.org/pub/firefox/releases/78.15.0esr/mac/en-US/
Note: After installation, it's recommended to avoid updating to newer versions, as they will not work on OS X 10.10.5.
Firefox Download for Mac 10105: A Step-by-Step Guide
Are you looking to download and install Firefox on your Mac? Look no further! In this post, we'll walk you through the process of downloading and installing Firefox on your Mac, as well as provide some additional information about the browser.
Why Choose Firefox?
Firefox is a popular web browser that offers a range of benefits, including:
Downloading and Installing Firefox on Mac
To download and install Firefox on your Mac, follow these steps:
Updating Firefox on Mac
To ensure you have the latest version of Firefox, follow these steps:
Firefox Version 10105: What's New?
Firefox version 10105 is a relatively minor update that includes some bug fixes and performance improvements. Some of the key changes include:
Conclusion
Downloading and installing Firefox on your Mac is a straightforward process that can be completed in just a few minutes. With its focus on speed, security, and customization, Firefox is a great choice for Mac users looking for an alternative to Safari or other browsers. If you're looking for a reliable and feature-rich browser, Firefox is definitely worth checking out!
Keeping Yosemite Alive: How to Download Firefox for Mac 10.10.5
If you’re still rocking a Mac with OS X Yosemite (10.10.5), you know the struggle. Modern websites are heavy, and Safari 8 feels like it's trying to run a marathon in flip-flops. You need a browser that still respects your hardware while letting you actually check your email.
Enter Firefox. While Mozilla has officially moved on to newer versions of macOS, you can still get a functional, stable version of Firefox for your Yosemite machine. Here is everything you need to know to get back online. The Best Version for Yosemite: Firefox 78 ESR
For users on Mac OS X 10.9, 10.10, and 10.11, the "end of the road" was Firefox version 78 Extended Support Release (ESR).
Why this version? It was the last major release to officially support Yosemite.
Is it safe? It received its final security update (version 78.15.0esr) on October 5, 2021. While it's more secure than the outdated version of Safari that comes with Yosemite, it no longer receives active patches. Step-by-Step: How to Download and Install
Since the main Firefox Download Page will likely try to give you the newest version (which won't open on your Mac), you need to grab the specific legacy installer.
Get the Installer: Navigate to the Mozilla Support Page for Legacy Mac Users or search for the Firefox 78.15.0esr dmg directly.
Open the DMG: Once the download finishes, double-click the Firefox 78.15.0esr.dmg file.
Install: Drag the Firefox icon into your Applications folder.
Launch: Open your Applications folder and double-click Firefox. You might see a warning that it was "downloaded from the internet"—just click Open. Pro Tips for Older Macs Browser Suggestions for Old Mac Laptop Yosemite 10.10.5
| Step | Action |
|------|--------|
| 1 | Open archive.mozilla.org/pub/firefox/releases/ |
| 2 | Click 78.15.0esr/ |
| 3 | Click mac/ |
| 4 | Click your language folder (e.g., en-US) |
| 5 | Download Firefox 78.15.0esr.dmg |
| 6 | Install, then disable automatic updates |
| 7 | Enjoy the latest possible update for Mac 10.10.5 |
Download the file:
Firefox 78.15.0esr.dmg (size ~85 MB). ⚠️ Recommendation : If possible, upgrade macOS or