shouldiuse.io

Report

Should I Use Add-ons for Firefox (en-US)?

addons.mozilla.org·Analyzed 1 hour ago·Based on 7 sources

Download Firefox extensions and themes. They’re like apps for your browser. They can block annoying ads, protect passwords, change browser appearance, and more.

Worth it

Worth it

Use it if you browse with Firefox — it's Mozilla's official, free extension store with a huge catalog.

Free official Firefox extension store — big catalog, zero cost, but useless without Firefox and quality varies wildly.

Confidence: Medium

$0

Starting price

Marketplace itself is free

Yes

Free extensions

Many open-source, e.g. uBlock Origin

Thousands

Catalog size

Themes alone: thousands of options

2017

Policy overhaul

Mozilla's major add-on changes

Value for money5

Free store, mostly free extensions

Ease of use4

One-click install; Firefox required first

Feature depth4

Extensions, themes, privacy, shopping categories

Support quality2

Per-developer; broken add-ons persist per reviews

Security posture3

Mozilla reviews exist; auto-published items listed pre-review

Pros

  • Completely free marketplace; many open-source extensions³
  • Huge catalog spanning privacy, shopping, search, and themes
  • Run by Mozilla, a non-profit, as the official Firefox store²
  • Staff picks and Recommended badges help discovery
  • Flagship blockers like uBlock Origin praised as CPU-light⁴

Cons

  • Requires Firefox; useless to non-Firefox browsers¹
  • Quality varies wildly; extensions break or get abandoned⁵
  • Auto-published add-ons may appear before editor review²
  • Popular blockers can break site features like YouTube playback⁶

Gotchas

  • highLock-in: extensions only work in Firefox; switching browsers means rebuilding your setup¹
  • mediumSome add-ons are auto-published and unreviewed when listed — check ratings and Recommended flags first²
  • mediumMaintenance depends on individual devs; updates can stop without notice⁵
  • lowAd blockers can conflict with sites — one breaks YouTube's playback speed menu⁶

Best for

  • Firefox users wanting ad blocking
  • Privacy-conscious browsers
  • Password manager and tracker-blocking needs
  • People who like customizing browser appearance

Not for

  • Chrome, Edge, or Safari users — add-ons require Firefox
  • Anyone expecting curated, enterprise-vetted software
  • Teams needing central licensing or procurement controls
  • Users unwilling to vet individual extensions themselves

Pricing

Free

$0

  • Marketplace browsing and installs free
  • Many extensions open-source
  • Firefox browser required

Security

No known public vulnerabilities found in the sources reviewed.

What users say

Users love free, lightweight blockers like uBlock Origin but regularly hit extensions that break, conflict with sites, or stop being maintained.

“The best thing. Does not slow Firefox at all. Minimal CPU usage”
— AMO review, uBlock Origin
“Suddenly stopped working. Can't add sites to blocklist, pages on the blocklist aren't blocked consistently.”
— AMO review, Block Site
“However, it's been interfering with the YouTube playback speed control menu.”
— AMO review, AdBlock for Firefox

Alternatives

Compare Add-ons for Firefox (en-US) with each alternative.

Full analysis

Based on 20+ public sources: AMO official pages, per-extension user reviews, and Wikipedia. Reviews are per-extension, not store-wide.

Sources

  1. Add-ons for Firefox homepageaddons.mozilla.org
    official
  2. About Firefox Add-onsaddons.mozilla.org
    official
  3. Extensions directoryaddons.mozilla.org
    official
  4. uBlock Origin reviewsaddons.mozilla.org
    review
  5. Block Site reviewsaddons.mozilla.org
    review
  6. AdBlock for Firefox reviewsaddons.mozilla.org
    review
  7. Add-on (Mozilla) - Wikipediaen.wikipedia.org
    news

Rate this review

Anonymous. You can change your vote.

Loading votes…

Ask a follow-up

Ask if a use case fits. Answers stay inside this report and its sources.