Firefox 103 Includes Performance Boost for Macs With 120Hz+ Displays

Mozilla has released a new version of Firefox that promises improved browsing performance on displays running at 120Hz and higher refresh rates, which should appeal to owners of 14-inch and 16-inch MacBook Pro models with ProMotion displays.

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Launched last October, Apple's redesigned ‌MacBook Pro‌ models with M1 Pro and M1 Max chips feature Liquid Retina XDR displays with ProMotion technology for adaptive refresh rates ranging from 24Hz to 120Hz.

When viewing a static webpage that doesn't require a high refresh rate, the ‌MacBook Pro‌'s display adopts the lower refresh rate to preserve battery life, but when gaming, scrolling, or doing other activities where a higher refresh rate will result in smoother content, the higher frame rates will kick in.

According to Mozilla's release notes, the latest Firefox 103 update brings improved performance on displays capable of refresh rates upwards of 120Hz, suggesting the 14-inch and 16-inch Macs with ProMotion stand to benefit.

As some readers will recall, soon after Apple launched 14-inch and 16-inch ‌MacBook Pro‌ models with Apple silicon last October, many users began reporting issues with stuttering, janky scrolling when browsing in Apple's Safari.

While some users reported noticing smoother Safari scrolling and performance on these Macs after upgrading to macOS Monterey 12.2, Apple has never officially confirmed that ProMotion is functional in its native browser for Mac. Therefore, anyone still unconvinced that they are seeing optimal refresh rates in Safari now at least has an alternative option to use a browser that should be capable of running ProMotion at full tilt.

In addition to the above, Firefox 103 also offers improved responsiveness on macOS during periods of high CPU load, which it achieves by switching to a modern lock API, according to the release notes.

Also new in this update is the ability to change the subtitles font size directly from within a Picture-in-Picture window, as well as support for subtitles on platforms including Funimation, Dailymotion, Tubi, Hotstar, and SonyLIV.

In other tweaks, required fields in PDFs are now highlighted, and there are a number of bugs and security vulnerabilities that have also been fixed. Firefox 103 for macOS is available now from the Mozilla website, where users can find a full list of changes.

Related Roundup: MacBook Pro
Buyer's Guide: MacBook Pro (Neutral)
Related Forum: MacBook Pro

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Top Rated Comments

contacos Avatar
37 months ago
I might be the only person on the planet that cannot notice a 120 Hz display ??‍♂️

Had it on my iPad Pro before moving to the iPad Air 4 and didn’t notice.
Went from first retina MBP 2012 to 14inch MBP and don’t notice
Score: 7 Votes (Like | Disagree)
IllinoisCorn Avatar
37 months ago

"Apple has never officially confirmed that ProMotion is functional in its native browser for Mac."

It's curious why Apple haven't confirmed this support for Pro motion on their own safari browser. I would have thought that they would have jumped all over this.

Maybe it's a compatibility issue with non Pro motion apple devices? I'm just wondering why?
Very, very strange. Of all the applications optimized, you'd think Safari would be right up there and you'd think Apple would talk about it.
Score: 6 Votes (Like | Disagree)
Leon Ze Professional Avatar
37 months ago
"Apple has never officially confirmed that ProMotion is functional in its native browser for Mac."

It's curious why Apple haven't confirmed this support for Pro motion on their own safari browser. I would have thought that they would have jumped all over this.

Maybe it's a compatibility issue with non Pro motion apple devices? I'm just wondering why?
Score: 6 Votes (Like | Disagree)
xxray Avatar
37 months ago
My favorite browser. I love Firefox for being privacy focused but still powerful, and Firefox Containers is a fantastic feature. I just wish their iOS apps had better UI so I could use the browser across all my devices.

I'm glad to see some performance and battery improvements on the Mac.
Score: 6 Votes (Like | Disagree)
MacsRgr8 Avatar
37 months ago

I might be the only person on the planet that cannot notice a 120 Hz display ??‍♂️

Had it on my iPad Pro before moving to the iPad Air 4 and didn’t notice.
Went from first retina MBP 2012 to 14inch MBP and don’t notice
I understand what you mean…
I have 49” UWD screen connected to my Mac Studio, and can choose 60 Hz, 100 Hz, 120 Hz… and TBH…. I cannot see any difference either… have it set to 120 Hz, simply so I can brag about it ?
Score: 4 Votes (Like | Disagree)
Unggoy Murderer Avatar
37 months ago

That’s disappointing!

I saw a comment in their forums where someone made an icon with a purple background and some parts of the fox sticking outside the frame. Looked really good.
Yeah there's a Bugzilla file for it: https://bugzilla.mozilla.org/show_bug.cgi?id=1648386

Just likely political nonsense that's preventing it from being implemented.
Score: 3 Votes (Like | Disagree)