Firefox 87 Introduces 'SmartBlock' Private Browsing Feature to Fix Websites Broken By Tracking Protections - MacRumorsOpen MenuShow RoundupsShow Forums menuVisit ForumsOpen Sidebar
Skip to Content

Firefox 87 Introduces 'SmartBlock' Private Browsing Feature to Fix Websites Broken By Tracking Protections

Mozilla has released Firefox 87 for Macs, Windows, and Linux machines, introducing a new intelligent tracker blocking mechanism called SmartBlock.

mozilla firefox banner
Since 2015, Firefox has included a built-in Content Blocking feature that automatically blocks third-party scripts, images, and other content from being loaded from cross-site tracking companies in Private Browsing windows and Strict Tracking Protection Mode.

Mozilla recognizes that the feature sometimes blocks legitimate elements of websites which can cause them to malfunction. SmartBlock aims to provide a solution to this problem without compromising user privacy. From the company's blog:

In building these extra-strong privacy protections in Private Browsing windows and Strict Mode, we have been confronted with a fundamental problem: introducing a policy that outright blocks trackers on the web inevitably risks blocking components that are essential for some websites to function properly. This can result in images not appearing, features not working, poor performance, or even the entire page not loading at all.

To reduce this breakage, Firefox 87 is now introducing a new privacy feature we are calling SmartBlock. SmartBlock intelligently fixes up web pages that are broken by our tracking protections, without compromising user privacy.

Mozilla says SmartBlock works by providing local stand-ins for blocked third-party tracking scripts that behave "just enough" like the original ones to make sure that the website works properly.

The stand-ins come built-in to Firefox, so no third-party content from the trackers is loaded by the browser, meaning they can't track users this way. According to the developers, SmartBlock will silently stand in for several common scripts classified as trackers on the Disconnect Tracking Protection List, and should provide a noticeable performance improvement while browsing.

The previous version of the browser introduced Total Cookie Protection, which is designed to stop cookies from tracking users across the web. Firefox 87, the latest update, is available now from the Mozilla website.

Popular Stories

Apple Event Logo

Apple Just Released a New Accessory

Monday May 4, 2026 8:13 am PDT by
Apple today released a new Pride Edition Sport Loop for the Apple Watch. The band features a rainbow design with 11 colors of woven nylon yarns. The new Pride Edition Sport Loop is available to order now on Apple.com and in the Apple Store app in 40mm, 42mm, and 46mm sizes, and it will be available at Apple Store locations starting later this week. In the U.S., the band costs $49. There...
iOS 27 on iPhone 17 1

iOS 27 Will Add These New Features to Your iPhone

Saturday May 2, 2026 8:43 am PDT by
Apple is expected to unveil iOS 27 during its WWDC 2026 keynote on June 8, and there are already many rumored features and changes for iPhones. The first developer beta of iOS 27 will likely be available immediately following the keynote, and a public beta typically follows in July. Following beta testing, the software update should be released to all users with a compatible iPhone in...
Apple Announces 2026 Pride Band Watch Face and iPhone Wallpaper Article 2

iOS 26.5 Coming Soon With These New Features

Monday May 4, 2026 8:40 am PDT by
iOS 26.5 is expected to be released next week, following more than a month of beta testing. The update is relatively minor, but there are a couple of new features and changes across the operating system that we have recapped below. iOS 26.5 lays the groundwork for end-to-end encryption for RCS in the Messages app and ads in the Apple Maps app, and it will include a new Pride wallpaper and a...

Top Rated Comments

67 months ago
I love their Container feature. You can create seperate "Cookie containers" for websites like Facebook, Youtube, etc.
That way you will keep your settings on these websites, but when you visit other websites, they can't abuse these cookies for tracking you, since they are not available there. Or a seperate container for e-banking.

It also allows you to have several containers for the same website, so you can use more than one user on the same website. Very convenient if you have a personal and a business Office 365 account, for example.

Requires the extension from firefox: "Multi-account Containers" to make full use of it.
Score: 32 Votes (Like | Disagree)
wanha Avatar
67 months ago
Never been much of a Firefox user, but I applaud Firefox for their actions on privacy.
Score: 25 Votes (Like | Disagree)
adrianlondon Avatar
67 months ago

Never been much of a Firefox user, but I applaud Firefox for their actions on privacy.
I'm surprised that Firefox actually runs faster on my MBA (Big Sur latest beta) than Safari, although I think that's due to the amount of stuff it natively blocks, along with uBlock Origin, rather than any rendering advantages.

Two main reasons I prefer Firefox. (1) cookie control especially with Containers and (2) the way going to previous pages while reading forums doesn't reload and send pages pack to the top. Oh, and (3) uBlock Origin.
Score: 21 Votes (Like | Disagree)
67 months ago
Dunno what's going on with Firefox lately, but it's ridiculously fast on my Mac.
Score: 13 Votes (Like | Disagree)
MJaP Avatar
67 months ago
I always use Firefox on my Windows PCs, I've found it fast and secure. Best alternative to Safari in my opinion.
Score: 9 Votes (Like | Disagree)
67 months ago

Faster than Safari?
Yes. Much. And if you go into about:config and up the process count from 8 to say ... 100 ... it's comically faster. This is easily faster than Chrome, Edge, Safari, and Brave. It's also incredibly smooth and stable. Just the whole feel of this version of Firefox is really great. This will be my main browser again for a while and I've been on brave for quite some time. Also, the ad blocking by default on iOS is really great, even blocks stuff Brave seems to miss. I don't see most ads on websites with Firefox when I set it to strict mode.

Another very important point ... I can open a million tabs in Firefox and nothing slows down. Like ... at all ... and all the websites are responsive. I'm honestly impressed. Hopefully these great strides in the Firefox experience keeps them from disappearing. We need more non-Chromium browsers competing with Google. Sucks that Google basically owns 90% of the browser use market with either Chrome or a Chromium-based browser ... so much that even Microsoft caved in. I'm glad to support Mozilla for not being like everyone else.
Score: 6 Votes (Like | Disagree)
Related Apple News: Check Who Using Iphone Hotspot Data | Airpods 4 Release Date | Airpods Deals | Use Edge Light Feature Facetime Macos | Apple Ai Strategy 2024