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Mozilla Firefox vs Violentmonkey

Mozilla Firefox logo

Mozilla Firefox

Technology

An independent web browser with its own rendering engine, funded almost entirely by search placement deals.

From
Free
Rated
-
Full reviewWebsite
Violentmonkey logo

Violentmonkey

Browser Extensions

Open source userscript manager

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: Mozilla Firefox roughly 85 per cent of Mozilla's revenue comes from search default placement deals, overwhelmingly with Google, so the organisation that competes with Chrome depends on Chrome's owner for its funding and any renegotiation lands on Firefox's engineering budget within a quarter.; Violentmonkey smaller script ecosystem compared to Tampermonkey which has larger user base and more available scripts
  • They diverge on capability: Mozilla Firefox covers Gecko engine, Violentmonkey covers Userscript support.
  • Prices and features above were last checked on 30 August 2026.

Where they differ

Only the attributes on which Mozilla Firefox and Violentmonkey actually diverge.

Attributes where Mozilla Firefox and Violentmonkey differ
AttributeMozilla FirefoxViolentmonkey
PlatformsWindows, macOS, Linux, iOS, AndroidChrome, Firefox, Edge
CategoryTechnologyBrowser Extensions
Founded20042013

Identical on both: starting price (Free), pricing model (Unknown), free tier (Yes), user rating (Not yet rated).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in Mozilla Firefox

  • Gecko engine
  • Full webRequest blocking
  • Total Cookie Protection
  • Container tabs
  • Extended Support Release
  • policies.json and ADMX
  • Built-in developer tools
  • Firefox Sync

Only in Violentmonkey

  • Userscript support
  • Clean interface
  • Cloud sync
  • Script editor
  • Chrome support
  • Firefox support
  • Edge support
  • Opera support

What people use each for

The jobs each tool is most often brought in to do.

Mozilla Firefox

  • Web development where you need to test against a non-Chromium engine before shipping, because Chromium-only testing hides real bugsnot Violentmonkey
  • Users who require a full-strength content blocker, which Chrome's Manifest V3 no longer permitsnot Violentmonkey
  • Managed fleets that need a browser on a slow release cadence with Group Policy control, using the ESR channelnot Violentmonkey
  • Handling several accounts on the same service at once through container tabs, without separate profiles or private windowsnot Violentmonkey

Violentmonkey

  • Run open-source userscripts to customize or automate web pagesnot Mozilla Firefox
  • Import scripts compatible with Greasemonkey and Tampermonkey formatsnot Mozilla Firefox
  • Sync scripts and settings across browsers via Dropbox, OneDrive, Google Drive, or WebDAVnot Mozilla Firefox
  • Batch import/export scripts as zip filesnot Mozilla Firefox

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

Mozilla Firefox

  • Roughly 85 per cent of Mozilla's revenue comes from search default placement deals, overwhelmingly with Google, so the organisation that competes with Chrome depends on Chrome's owner for its funding and any renegotiation lands on Firefox's engineering budget within a quarter.
  • Desktop market share sits at a few per cent, so commercial sites are tested against Chrome and Safari and a Firefox-only rendering or WebRTC bug is triaged as low priority by the site owner, leaving you with the workaround.
  • On iOS and iPadOS the browser is a WebKit shell required by Apple's rules, so it delivers the interface and Sync but none of the engine, extension or tracking-protection behaviour that make Firefox worth choosing on desktop.
  • Mozilla declines to implement several hardware-facing APIs on principle, including WebUSB, WebSerial, Web Bluetooth and WebHID, so a web application that talks to a device simply does not run and no configuration flag changes that.
  • Enterprise management is limited to policies.json and ADMX templates; there is no first-party equivalent of Chrome Browser Cloud Management, so fleet-wide reporting on versions and extensions requires third-party tooling you have to buy or build.
  • Mozilla repeatedly ships decisions its own user base objects to, such as enabling Privacy Preserving Attribution by default and the 2025 Terms of Use rewrite, and reversals arrive after the news cycle, so deploying it on a privacy argument means owning the communications work each time.

Violentmonkey

  • Smaller script ecosystem compared to Tampermonkey which has larger user base and more available scripts
  • Less marketing and visibility results in lower adoption compared to more widely-known alternatives
  • Community maintenance model means slower feature development compared to commercial alternatives

Pricing, plan by plan

Mozilla Firefox

Free

No published plan breakdown. See the Mozilla Firefox review.

Violentmonkey

Free

No published plan breakdown. See the Violentmonkey review.

Which should you pick?

Choose Mozilla Firefox if

  • You need gecko engine.
  • You want to start without paying.
  • You work on Windows, macOS, Linux, iOS, Android.
  • You also want full webrequest blocking.
Mozilla Firefox review

Choose Violentmonkey if

  • You need userscript support.
  • You want to start without paying.
  • You work on Chrome, Firefox, Edge.
  • You also want clean interface.
Violentmonkey review

Questions people ask

Is Mozilla Firefox or Violentmonkey better?
Neither clearly leads. Mozilla Firefox starts at Free and Violentmonkey at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Mozilla Firefox or Violentmonkey?
Mozilla Firefox starts at Free and Violentmonkey at Free.
Does Mozilla Firefox or Violentmonkey run on more platforms?
Mozilla Firefox runs on Windows, macOS, Linux, iOS, Android. Violentmonkey runs on Chrome, Firefox, Edge.
Can I use Mozilla Firefox for free?
Both have a free tier, so you can try either at no cost before committing.
What is Mozilla Firefox best used for?
Mozilla Firefox is most often used for web development where you need to test against a non-chromium engine before shipping, because chromium-only testing hides real bugs, users who require a full-strength content blocker, which chrome's manifest v3 no longer permits, managed fleets that need a browser on a slow release cadence with group policy control, using the esr channel, handling several accounts on the same service at once through container tabs, without separate profiles or private windows. Of those, web development where you need to test against a non-chromium engine before shipping, because chromium-only testing hides real bugs and users who require a full-strength content blocker, which chrome's manifest v3 no longer permits are not what Violentmonkey is typically brought in for.
What can Mozilla Firefox do that Violentmonkey cannot?
Mozilla Firefox covers Gecko engine, Full webRequest blocking, Total Cookie Protection, Container tabs. Violentmonkey covers Userscript support, Clean interface, Cloud sync, Script editor.

Answered from the vendors’ own pages

Mozilla Firefox: Does uBlock Origin still work on Firefox?

Yes. Firefox has kept the blocking webRequest API that Chrome removed with Manifest V3, so uBlock Origin runs with its full rule set rather than the cut-down Lite version Chrome requires.

Violentmonkey: Is Violentmonkey open-source?

Yes. Violentmonkey is fully open-source and available on GitHub, making it free to use and community-maintained unlike Tampermonkey which has a larger proprietary ecosystem.

Source
Mozilla Firefox: Is Firefox on iPhone the same browser?

No. Apple's platform rules require it to use WebKit, so on iOS and iPadOS you get Firefox's interface, Sync and bookmarks on top of Safari's engine. The privacy and extension behaviour are not the same.

Violentmonkey: What browsers does Violentmonkey support?

Violentmonkey works on browsers with WebExtensions support, including Chrome, Firefox, Edge, and other Chromium-based browsers.

Source
Mozilla Firefox: How is Mozilla funded, and does that matter?

Mainly by payments for making a search engine the default, with Google as the dominant payer. It matters because it is a single-source dependency on a direct competitor, and it has been the subject of antitrust litigation whose outcome Mozilla does not control.

Violentmonkey: How does Violentmonkey compare to Tampermonkey in performance?

Community benchmarks show Violentmonkey uses about 15 to 30 percent less RAM on Chrome compared to Tampermonkey when managing many open tabs.

Source
Mozilla Firefox: Can I manage it across a company fleet?

Yes, through policies.json or Windows Group Policy with the ADMX templates, and the ESR channel gives you a roughly yearly major version instead of four-weekly. There is no first-party cloud management console, so reporting needs other tooling.

Violentmonkey: What is the current version of Violentmonkey?

Violentmonkey reached version 2.46.0 as of July 31, 2026, with active ongoing development and regular updates to the open-source project.

Source
Mozilla Firefox: Will every site work in it?

Most will. The exceptions cluster around sites tested only in Chrome, legacy enterprise applications, and anything using WebUSB, WebSerial, Web Bluetooth or WebHID, which Firefox does not implement at all.

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Related pages

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