Yab

Opera Neon vs Firefox

We make Yab, the third column.facts checked Oct 9 ↓

Opera Neon is Opera’s agent browser for Mac and Windows. Its own agents act in your live session on a $19.90 plan, and since August 2026 outside agents like Claude Code can use it free through its MCP Connector.

Firefox is Mozilla’s open-source browser on its own engine, Gecko, on every desktop and phone. Its AI is optional: a Smart Window beta and a sidebar chatbot, all behind one switch.

The short answer

Pick Opera Neon
  • if you want Claude Code or another MCP client to use a real signed-in browser, free
  • if you want one plan for an in-browser agent, deep research and making apps and media
  • if you want a VPN and an ad blocker built in
Pick Firefox
  • if you want an open-source browser that isn’t Chromium
  • if you want AI off by default, or gone with one switch
  • if you want a free browser VPN, where it is offered
Or Yabours
  • if you miss Arc and want spaces, pins and folders kept, on a Mac
  • if you already pay for Claude or ChatGPT and want it to work in your signed-in tabs
  • if you want Claude Code, Codex or Cursor to drive a real browser over MCP

At a glance

Opera Neon and Firefox, with Yab beside them for a Mac.

Opera Neon vs Firefox
WhatOpera NeonFirefoxYab
Made byOperaMozillaSerafim Korablev
StatusUpdatedUpdatedUpdated
Runs onMac and WindowsMac, Windows, Linux, iPhone and AndroidMac
Phone appNone yet; Opera says a mobile version will come, no date giveniPhone, iPad and Android; syncs tabs, bookmarks, passwords and historyNot yet
PriceFree, and free for outside agents; Opera’s own agents $19.90/monthFree; its built-in VPN is free up to 50 GB a monthFree; its AI runs on your own Claude or ChatGPT plan
AIAn agent that works in pages, on its own AI serviceChat about pages, on its own AI or yoursAn agent that works in pages, on your Claude or ChatGPT plan
Driven by outside agentsMCP and a command lineMCPMCP and a command line
EngineChromiumGeckoWebKit
Tabs down the sideNot statedA settingYes
SpacesYesNoYes
Split ViewNot statedYesYes
ExtensionsNot statedFirefox add-onsChrome Web Store
Ad blockerBuilt inNoBuilt in
Open sourceNoYesNo

Checked October 9, 2026 on each maker’s own pages, linked under Sources. Prices are per month, in US dollars.

Where they differ

What separates them, area by area. Where one plainly has more, it says who; where it comes down to taste, it says so.

AIOpera Neon leads

Only Opera Neon has an agent that clicks, types and finishes tasks in your pages. Neon Chat talks about your tabs, Neon Do acts in your live session, research agents dig, and Make builds apps and media on Opera’s servers. Firefox’s Smart Window beta chats with tabs you share and groups them, and a sidebar chatbot can use Claude, ChatGPT, Gemini, Le Chat or Copilot; it can’t click or fill forms, and one switch turns all AI off.

Agents like Claude Code and CodexOpera Neon leads

Opera Neon can be driven over MCP and a command line, through its MCP Connector, read-only unless you allow more, and opera-browser-cli. Firefox can be driven over MCP, through Mozilla’s Firefox DevTools MCP, which starts its own Firefox.

Tabs and windowsFirefox leads

Opera Neon has spaces. Firefox has tabs down the side as a setting, Split View, folders in the sidebar and tabs that sleep.

PriceFirefox leads

Opera Neon: Free, and free for outside agents; Opera’s own agents $19.90/month. Firefox: Free; its built-in VPN is free up to 50 GB a month.

Where it runsFirefox leads

Opera Neon runs on Mac and Windows. Firefox runs on Mac, Windows, Linux, iPhone and Android. On a Mac, Firefox needs macOS 10.15 or later. Opera Neon has no phone app yet: Opera says a mobile version will come, no date given. On the phone, Firefox: iPhone, iPad and Android; syncs tabs, bookmarks, passwords and history.

Engine and extensionsa matter of taste

Opera Neon is built on Chromium, as Chrome is; Firefox on Gecko, Firefox’s engine. Opera Neon takes no extensions, Firefox from Firefox’s add-ons.

Privacyeven

Opera Neon has an ad blocker built in and a VPN. Page content used with Neon’s AI goes to Opera’s and OpenAI’s servers, kept up to 365 days; passwords, cards and cookies stay on your device. Firefox has a VPN and open code. Smart Window sends prompts and what you share through Mozilla’s servers to partner models; Mozilla says it keeps no chat logs without permission and doesn’t train on them.

What their pages don’t lead with

Real limits, from the makers’ own words and our own use.

Opera Neon

  • Opera’s own agents need the $19.90 a month plan
  • Mac and Windows only; the phone version isn’t out
  • Its AI and the MCP Connector need an Opera account
  • Page content used with its AI goes to Opera’s and OpenAI’s servers, kept up to 365 days

Firefox

  • Its Smart Window AI is a beta in the US, Canada and France and needs a Mozilla account
  • Its AI can’t click, fill forms or buy for you
  • The free VPN covers the browser only, up to 50 GB a month, in a few countries
  • Firefox add-ons only, not the Chrome Web Store

Yab, honestly

  • Mac only: macOS 15.4 or later, no Windows, iPhone or Android
  • New: first released in September 2026
  • Its AI needs a Claude or ChatGPT plan; ChatGPT’s free plan may work with low limits
  • WebKit, as in Safari: a site tested only in Chrome can misbehave
  • Closed source

What changed lately

  • September 16, 2026Firefox: Smart Window beta expanded from the US and Canada to France
  • August 12, 2026Opera Neon: Free plan: outside agents can use Neon without a subscription
  • May 12, 2026Opera Neon: opera-browser-cli command line released
  • March 31, 2026Opera Neon: MCP Connector lets outside AI clients act in Neon
  • March 24, 2026Firefox: Firefox 149 added split view and a free built-in VPN
  • February 24, 2026Firefox: Firefox 148 added AI Controls with a switch that blocks all AI features

Questions

Is Opera Neon free?

Yes, with limits on its AI. Free, and free for outside agents; Opera’s own agents $19.90/month.

Is Firefox free?

Yes. Free; its built-in VPN is free up to 50 GB a month.

Which has an AI agent, Opera Neon or Firefox?

Opera Neon. Neon Chat talks about your tabs, Neon Do acts in your live session, research agents dig, and Make builds apps and media on Opera’s servers. Firefox’s Smart Window beta chats with tabs you share and groups them, and a sidebar chatbot can use Claude, ChatGPT, Gemini, Le Chat or Copilot; it can’t click or fill forms, and one switch turns all AI off.

Do Opera Neon and Firefox run on Windows?

Yes, both. Opera Neon runs on Mac and Windows; Firefox on Mac, Windows, Linux, iPhone and Android.

Do Opera Neon and Firefox have phone apps?

Firefox does. Opera Neon has no phone app yet: Opera says a mobile version will come, no date given. On the phone, Firefox: iPhone, iPad and Android; syncs tabs, bookmarks, passwords and history.

Is there a third option on a Mac?

Yab, Yet Another Browser, is free for the Mac: tabs down the side with spaces, folders and Split View, as in Opera Neon; an agent in your signed-in tabs like Opera Neon’s, on the Claude or ChatGPT plan you already pay for. Claude Code, Codex and any MCP client can drive it too. It runs on WebKit, the engine Safari uses, and takes Chrome extensions. It is Mac only, and new.

More comparisons

Opera Neon vs DiaOpera Neon vs CometOpera Neon vs AtlasAside vs Opera NeonOpera Neon vs ChromeOpera Neon vs SafariOpera Neon vs EdgeOpera Neon alternativesYab vs Opera NeonFirefox vs ChromeFirefox vs SafariFirefox vs EdgeBrave vs FirefoxOpera vs FirefoxArc vs FirefoxDia vs FirefoxFirefox alternativesYab vs Firefox
Sources, read October 9, 2026. Something out of date? Write to hello@serafimlabs.io and we fix it.

Yab, Yet Another Browser.

Free for the Mac. Arc’s sidebar, your own Claude or ChatGPT as the agent, Chrome extensions on WebKit.

it’s freeMove from FirefoxDownload