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.

mozilla firefox banner fixed
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 (Caution)
Related Forum: MacBook Pro

Popular Stories

iPhone 17 Pro Dark Blue and Orange

iPhone 17 Release Date, Pre-Orders, and What to Expect

Thursday August 28, 2025 4:08 am PDT by
An iPhone 17 announcement is a dead cert for September 2025 – Apple has already sent out invites for an "Awe dropping" event on Tuesday, September 9 at the Apple Park campus in Cupertino, California. The timing follows Apple's trend of introducing new iPhone models annually in the fall. At the event, Apple is expected to unveil its new-generation iPhone 17, an all-new ultra-thin iPhone 17...
iPhone 17 Pro Iridescent Feature 2

iPhone 17 Pro Clear Case Leak Reveals Three Key Changes

Sunday August 31, 2025 1:26 pm PDT by
Apple is expected to unveil the iPhone 17 series on Tuesday, September 9, and last-minute rumors about the devices continue to surface. The latest info comes from a leaker known as Majin Bu, who has shared alleged images of Apple's Clear Case for the iPhone 17 Pro and Pro Max, or at least replicas. Image Credit: @MajinBuOfficial The images show three alleged changes compared to Apple's iP...
iphone 16 pro ghost hand

iPhone 17 Pro: 5 Reasons Not to Upgrade This Year

Monday September 1, 2025 4:35 am PDT by
Apple will launch its new iPhone 17 series this month, and the iPhone 17 Pro models are expected to get a new design for the rear casing and the camera area. But more significant changes to the lineup are not expected until next year, when the iPhone 18 models arrive. If you're thinking of trading in your iPhone for this year's latest, consider the following features rumored to be coming to...
xiaomi apple ad india

Apple and Samsung Push Back Against Xiaomi's Bold India Ads

Friday August 29, 2025 4:54 am PDT by
Apple and Samsung have reportedly issued cease-and-desist notices to Xiaomi in India for an ad campaign that directly compares the rivals' devices to Xiaomi's products. The two companies have threatened the Chinese vendor with legal action, calling the ads "disparaging." Ads have appeared in local print media and on social media that take pot shots at the competitors' premium offerings. One...
iOS 18 on iPhone Arrow Down

Apple Preparing iOS 18.7 for iPhones as iOS 26 Release Date Nears

Sunday August 31, 2025 4:35 pm PDT by
Apple is preparing to release iOS 18.7 for compatible iPhone models, according to evidence of the update in the MacRumors visitor logs. We expect iOS 18.7 to be released in September, alongside iOS 26. The update will likely include fixes for security vulnerabilities, but little else. iOS 18.7 will be one of the final updates ever released for the iPhone XS, iPhone XS Max, and iPhone XR,...

Top Rated Comments

contacos Avatar
41 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
41 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
41 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
41 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
41 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
41 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)