Three browsers control roughly 95% of web usage: Chrome, Safari, and Edge. All three use Blink or WebKit as their rendering engine. The only exception with meaningful market share is Firefox, which runs on Gecko.

That distinction matters more than browser market share numbers suggest.

Why One Independent Engine Matters

Web standards are not handed down from a neutral body. They are negotiated, and the negotiation is heavily influenced by which browsers implement features first, how they implement them, and what performance characteristics they optimize for.

When Google implements a feature in Blink - which powers Chrome, Edge, Brave, Vivaldi, Opera, and Samsung Internet - it becomes a de facto web standard regardless of what the W3C says. Developers test in Chrome and assume other browsers will follow.

Firefox’s independent implementation of web standards is not sentimental. It is the mechanism that prevents any single company from owning the web’s behavior. When Google proposed FLoC as a tracking replacement, Firefox refused to implement it, which contributed to the backlash that killed the proposal. Without Firefox holding that line, it is harder to imagine the outcome being different.

Gecko also regularly ships web platform features before Blink, pushing the platform forward. CSS Grid, container queries, and several CSS math functions were in Firefox before Chrome.

The Market Share Collapse

Firefox had 34% global market share in 2010. As of early 2025, it sits around 3-4%.

The causes are straightforward:

  • Chrome launched with a substantially faster JavaScript engine (V8) at a time when JS performance was the primary browser benchmark
  • Google’s search page and Google Docs started showing Chrome download prompts to Firefox users
  • Mozilla was slow to ship a 64-bit Firefox
  • The Android browser market consolidated around Chrome before Firefox Mobile gained traction
  • iPhone users cannot install non-WebKit browsers (Apple’s App Store policy until recently in the EU)

Mozilla did not lose to a better browser in the abstract. It lost to a competitor with unlimited resources and control of the most-visited website on the internet.

Where Mozilla Made Unforced Errors

This is where the criticism gets specific.

Pocket Was a Distraction

Mozilla acquired Pocket in 2017 and integrated it into Firefox. Pocket is a read-it-later service. It has nothing to do with browser security, privacy, or standards. The engineering and product resources spent on Pocket maintenance and integration could have gone toward catching up on performance or developer tools.

The CEO Controversy Killed Momentum

In 2014, Mozilla appointed Brendan Eich as CEO, then accepted his resignation 11 days later after the controversy over his past political donations. The episode was handled poorly regardless of which side you were on. It created a story about Mozilla that had nothing to do with browsers and distracted from the product.

VPN and Other Subscription Services

Mozilla now sells a VPN, a relay email service, and a password manager. All three compete in crowded markets dominated by specialists. Building a VPN business while Firefox loses a percentage point of market share every year is a strange strategic priority.

Layoffs While Diversifying

Mozilla laid off 25% of its staff in 2020 and another round in 2023, while continuing to fund non-browser products. The message this sent - even if the accounting justified it - was that the browser was not the priority.

What Google Pays For the Problem to Stay Manageable

Mozilla’s primary revenue source is a deal with Google to make Google the default search engine in Firefox. This deal has historically been worth $400-500 million per year.

That is Google paying its only real browser competitor to stay alive, which is a strange situation. Mozilla needs the money to operate. Google presumably prefers Firefox to exist as a fig leaf for antitrust regulators. The arrangement works for both parties but creates an obvious dependency that is uncomfortable.

If Google ever ended or significantly reduced that deal, Mozilla would face an existential crisis.

The Case for Firefox Right Now

Despite all of this, Firefox is a genuinely excellent browser in 2025:

  • Best built-in privacy controls of any major browser
  • uBlock Origin works at full capability (Chrome’s Manifest V3 limitations have weakened it)
  • Multi-account containers are a feature no other browser offers natively
  • Total Cookie Protection is the most effective cross-site tracking prevention available
  • Developer tools have improved significantly in the last two years

If you care about not being tracked and you want your browser to have genuinely independent interests from an advertising company, Firefox is the correct choice. It is faster than it has ever been and the memory usage issues of the Firefox 50s era are mostly gone.

Bottom Line

Firefox deserves to survive not because nostalgia but because the web needs a credible independent implementation of web standards to avoid becoming Google’s proprietary platform with an HTML skin. The alternative - a web where every browser engine answers to either Google or Apple - is worse for users, developers, and the open internet.

Mozilla has made that fight harder with years of strategic distraction. But the browser itself is good. Use it, contribute to it, and pay for Mozilla services if you use them. The cost of Firefox disappearing is higher than most people realize until after it happens.