Best Firefox Extensions in 2026: What to Install and Why

Firefox extensions turn a plain browser into whatever you need it to be — an ad-free reading tool, a password vault, a place where forty tabs from a late-night research binge don’t just vanish. If you’ve typed “browser extension for Firefox” into a search bar and gotten lost in Mozilla’s store, this guide sorts it out: where to find real Firefox addons, how to install and manage them, which ones are worth your toolbar space, and where Firefox’s rules are genuinely different from Chrome’s. (Some people search for “Foxfire extensions”. That’s just Firefox, misheard.) We’ll also cover what happens on your phone, because Firefox extensions on iOS don’t behave the way you’d expect. By the end you’ll know exactly which firefox browser extensions to install first, and which ones to skip.

What Are Firefox Extensions, and Why Install Them?

Firefox extensions are small add-on programs, installed from Mozilla’s official store, that add features Firefox doesn’t ship with by default — ad blocking, password management, grammar checking, or saving your open tabs as a named session. Firefox itself is deliberately lean out of the box, so extensions do a lot of the heavy lifting people expect from a modern browser.

The appeal is that you pick exactly what you need instead of carrying features you’ll never touch. Someone who writes for a living might add a grammar checker and a distraction blocker. Someone who researches for a living ends up with a tab manager and a read-it-later tool. Firefox doesn’t force either approach. It just gives you a store and lets you build the browser you actually want.

In practice, most people end up pulling from four buckets: something that blocks ads and trackers, something that manages passwords, something for writing or reading, and something that keeps tabs from disappearing when the browser hiccups. You don’t need one from every bucket — plenty of Firefox users run for years with just an ad blocker and nothing else. The mistake is installing five things that do almost the same job, which adds background processes without adding real capability.

Where that store lives, and what runs where, depends on which device you’re on. Here’s the short version before we get into the details.

Firefox vs Chrome extensions. Firefox extensions and Chrome extensions are built for different stores and, in most cases, don’t install directly from one to the other. If you’re switching from Chrome, search addons.mozilla.org for the Firefox equivalent rather than trying to drag a .crx file over.

Where Do You Find the Firefox Extensions Store?

Firefox’s extension store is addons.mozilla.org, usually called AMO for short. It’s the only official source for Firefox extensions and themes. Mozilla describes it simply: extensions are like apps for Firefox, and they add features to make browsing faster, safer, or just more fun (addons.mozilla.org).

You can browse AMO by category (privacy and security, productivity, tab management, shopping, and so on) or search for something specific by name. Every listing shows a description, screenshots, a version number, and user ratings, so you can get a sense of an extension before you commit to it. Unlike some stores that bury the install button behind ads or unrelated recommendations, AMO keeps the page focused: one clear button, one clear description, and the permissions it needs.

Ratings are worth a glance before you install, but don’t treat the star average as the whole story. A four-star extension with three reviews tells you less than a four-star extension with hundreds, and a listing that hasn’t been updated in a couple of years deserves extra scrutiny even if the description still reads fine. None of this takes more than the few seconds it takes to scroll past the description to the version history.

If you’re comparing the Firefox extensions store to what you’re used to on Chrome or Edge, the biggest practical difference is curation, which we’ll get into a couple of sections down. For now, just know that AMO is the one place you should ever download a Firefox extension from — not a random download link, not a .xpi file someone emailed you.

How Do You Install a Firefox Extension?

You install a Firefox extension by finding it on addons.mozilla.org and clicking “Add to Firefox,” then approving the permissions it asks for. The whole process takes under a minute for most extensions.

That’s it — no restart required in most cases, and the extension’s icon typically shows up near your address bar right away. If the extension turns out not to be what you expected, there’s no real commitment beyond those few clicks — removing it later is just as fast as installing it was. That’s worth remembering when you’re comparing two or three similar tools instead of trying to pick the “best” one from reviews alone: install your top pick, use it for a day, and swap it out if it’s not pulling its weight.

If you’ve got a lot of tabs open while you’re browsing AMO looking for the right tool, it’s worth knowing your way around Firefox’s keyboard shortcuts for jumping between them; our Firefox shortcuts guide covers the ones people use.

Read the permissions dialog once. It only takes a few seconds, and it’s the single best signal you have before installing. A simple color-changing theme shouldn’t be asking for access to your browsing data on every site.

How Do You Manage or Remove Firefox Extensions?

You manage Firefox extensions from about:addons, which you reach either by typing that directly into the address bar or through the Firefox menu’s Add-ons and themes item. From there you can see everything you’ve installed in one list.

Disabling is the better first move if you’re troubleshooting. It keeps your settings and saved data intact in case the extension wasn’t the problem. Removing wipes it out entirely, which is fine once you’re sure you don’t need it. Either way, about:addons is also where you’ll spot extensions you forgot you installed months ago and don’t recognize anymore, which is worth checking every so often.

It helps to treat about:addons as something to revisit on a schedule, not just when something breaks. A common pattern: you install a coupon-finder extension during a big shopping event or a PDF tool for one project, then never touch it again. None of those are dangerous by themselves, but months of accumulated one-off installs is exactly the clutter that makes troubleshooting harder later, since you’ve got more variables to rule out when something does go wrong.

What Makes Firefox’s Add-on Store Different From Chrome’s?

Firefox’s extensions behave differently from Chrome’s in one significant way: Mozilla’s Manifest V3 still supports the blocking webRequest API and event-page background scripts, the same tools ad blockers and privacy extensions have relied on for years (Mozilla Add-ons Blog). Mozilla has been explicit that its version of Manifest V3 “diverges where we think it matters” from Chrome and Safari’s approach (Mozilla Extension Workshop).

The other difference is curation. Firefox has a Recommended Extensions program — a badge given to add-ons that meet “the highest standards of security, functionality, and user experience,” after Firefox staff review them manually and keep checking with automated scans and periodic technical reviews (Mozilla Extension Workshop). It’s not the only sign of a trustworthy extension, but it’s a reasonable shortcut when you’re choosing between five ad blockers that all claim to be the best.

In practical terms, this means the ad blockers and privacy tools you’re used to on Firefox should keep behaving the way they always have, without a sudden loss of features. If you’ve read that some browsers’ ad blockers got noticeably weaker after their old extension platform was phased out, that’s specifically a Manifest V2-to-V3 story that played out differently in Chrome — Firefox keeping the blocking webRequest API means that particular trade-off mostly doesn’t apply here.

What Are the Best Firefox Addons for Privacy and Security?

The best Firefox addons for privacy and security fall into a handful of categories, and you generally only need one from each: a tracker/ad blocker, a password manager, and maybe a privacy-focused search or anti-fingerprinting tool if you’re particularly cautious. Piling on five overlapping privacy extensions tends to slow Firefox down without adding much real protection.

Broad permissions deserve a second look. An extension that asks to “read and change all your data on all websites” isn’t automatically bad — plenty of legitimate tools need that to work. But it’s worth asking whether the extension’s job requires it before you approve.

Stack too many privacy tools and you’ll notice pages breaking, forms not submitting, or Firefox just feeling slower for no obvious reason. Pick the one or two that address a real problem you have, install those, and leave the rest.

A common combination causes exactly this: a password manager and a separate form-filling extension both trying to populate the same checkout field, or two ad blockers each rewriting a page in slightly different ways. Neither extension is broken; they’re just stepping on each other. If a site starts behaving oddly right after you add something new, disabling the newest addition first (before assuming the website itself is at fault) usually finds the culprit faster.

What Are the Best Firefox Extensions for Productivity and Tabs?

The best Firefox extensions for productivity are the ones that solve a problem you have, not the ones with the flashiest listing page. If you’re a chronic tab-hoarder, a tab and session manager earns its keep faster than almost anything else you could install.

• Tab & session managers. Save groups of open tabs as named sessions you can close and reopen later without losing anything.
• Read-it-later tools. Send an article or page to a reading queue instead of leaving the tab open “for later” forever.
• Focus & writing tools. Block distracting sites or check your writing while you work, without adding another app to switch to.

This is where BelayTab fits. It’s a free Firefox extension that saves any window (or just the tabs you select) as a named session with one click or Ctrl + Shift + S (Cmd + Shift + S on Mac). Tab groups, pinned tabs, and tab order all come along for the ride, and you can restore into a new window or the one you’re already in.

Large sessions restore in batches of 20 tabs at a time, so opening a window with sixty saved tabs doesn’t try to load everything at once and choke the browser. You can also save a single tab instead of a whole window, handy for pulling one reference page out of a cluttered window without dragging the other thirty tabs along with it. None of this requires setup beforehand — automatic snapshots run in the background regardless.

Firefox already has a built-in way to bring back your last session after closing the browser — our guide to restoring your last Firefox session covers that. Where it runs out is anything beyond “the last time you closed the browser”: naming specific projects, keeping several sessions side by side, or getting a window back from three days ago. That’s the gap a dedicated tab and session manager like BelayTab covers, and it’s worth pairing with Firefox’s tab groups if you already organize tabs that way.

Can You Use Firefox Extensions on Android?

Yes — Firefox for Android installs extensions from the same addons.mozilla.org catalogue as desktop Firefox, not a separate, smaller mobile store. Mozilla opened the full AMO catalogue to Firefox for Android in December 2023 (support.mozilla.org), which put it well ahead of most mobile browsers on this front.

That matters more than it might sound, because extension support on phones is genuinely rare. Chrome on Android and iPhone doesn’t run extensions at all — the mobile Chrome Web Store just offers an “Add to Desktop” option that queues the extension for your computer instead. Our guide to Chrome extensions on mobile walks through what that means if you’ve been searching for a workaround.

Kiwi Browser is gone. If you remember Kiwi Browser as a way to run Chrome extensions on Android, it was discontinued and pulled from Google Play in early 2025. Firefox for Android is now one of the more reliable ways to get real extensions on an Android phone.

Installing on Android works the same way it does on desktop: search or browse AMO from inside the Firefox app, tap to add, and approve the permissions. There’s no separate approval process or reduced feature set for the mobile version of most extensions.

That consistency is worth pointing out because it’s unusual. Most mobile browsers either skip extensions entirely or offer a stripped-down selection curated by the vendor, so Firefox for Android giving you the same catalogue you’d use on a laptop is a real advantage if extensions matter to how you browse. It also means a tab or session manager you rely on at your desk is the same one you’d reach for on your phone, not a second tool with a different interface.

Do Firefox Extensions Work on iOS (iPhone and iPad)?

No — Firefox for iOS can’t run extensions at all, because Apple’s WebKit rules for every browser on iPhone and iPad block it, and that includes Firefox even though it looks and feels similar to the desktop version (support.mozilla.org). This is a common source of confusion for people searching “firefox extensions ios” expecting the same store they use on their laptop.

It’s not a Firefox-specific limitation — Apple requires every iOS browser to use its WebKit engine, and that engine doesn’t allow the kind of extension system Firefox runs on desktop and Android. If extensions are the deciding factor for your phone browser, Safari is currently the more capable option on iPhone: it gets extensions from the App Store, and you enable them under Settings > Apps > Safari > Extensions. Our guide to the best Safari extensions covers what’s available there.

Don’t expect AMO on your iPhone. Searching for Firefox add-ons inside Firefox for iOS won’t turn anything up, no matter how you phrase it. This is an Apple platform rule, not something Mozilla can fix on its end.

It’s also worth knowing this isn’t unique to Firefox — every browser on iPhone and iPad, including Chrome, ultimately runs on Apple’s WebKit engine, and WebKit enforces the extension restriction. Switching to a different browser app on your iPhone in search of Firefox-style extensions won’t get you there either, unless that browser is Safari itself, which gets its extensions through the App Store instead of a desktop-style add-on store.

How Do You Keep Extensions From Slowing Firefox Down or Breaking It?

You keep extensions from slowing Firefox down by installing only what you use, checking about:addons periodically for anything you forgot about, and disabling extensions one at a time when something seems off rather than guessing. A browser carrying fifteen half-used extensions is going to feel heavier than one carrying four.

Disable, don’t reinstall, when troubleshooting. If Firefox starts freezing, crashing, or acting strangely after adding something new, disable your most recent extensions one by one instead of reinstalling Firefox from scratch. It’s faster, and it tells you exactly which one caused it. Our Firefox keeps crashing guide has more general fixes if disabling extensions doesn’t solve it.

Extensions can also fail quietly — an ad blocker that stops updating its filter lists, or a password manager that stops syncing without telling you. Checking about:addons every few months for anything outdated or unfamiliar is a cheap habit that saves you from bigger headaches later.

Updates are usually where things go quietly wrong rather than loudly wrong — an extension keeps running but stops doing its job, which is easy to miss until you notice ads back on a page an ad blocker used to clean up, or a password manager that’s stopped offering to save new logins. If you can’t remember the last time you watched one of your extensions doing its job, that’s reason enough to open about:addons and take stock.

None of this protects the one thing extensions can’t: your actual open tabs, if Firefox crashes hard or your laptop just dies mid-session. That’s a different problem, and it’s the one BelayTab is built to solve.