YabOpera vs Firefox
Opera One is Opera’s free Chromium browser on every desktop and phone, with a free browser VPN, an ad blocker, messengers in the sidebar and Opera AI. Its agents are in a separate browser, Opera Neon.
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
- if you want a free browser VPN and an ad blocker built in
- if you keep WhatsApp, Telegram or Slack open in a sidebar
- if you sort work into workspaces, Tab Islands and split screen
- 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
- 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 and Firefox, with Yab beside them for a Mac.
| What | Opera | Firefox | Yab |
|---|---|---|---|
| Made by | Opera | Mozilla | Serafim Korablev |
| Status | Updated | Updated | Updated |
| Runs on | Mac, Windows, Linux, iPhone and Android | Mac, Windows, Linux, iPhone and Android | Mac |
| Phone app | iPhone, iPad and Android; syncs tabs, bookmarks and Speed Dials with an Opera account | iPhone, iPad and Android; syncs tabs, bookmarks, passwords and history | Not yet |
| Price | Free, with Opera AI and a browser VPN; VPN Pro is paid | Free; its built-in VPN is free up to 50 GB a month | Free; its AI runs on your own Claude or ChatGPT plan |
| AI | Chat about pages, on its own AI service | Chat about pages, on its own AI or yours | An agent that works in pages, on your Claude or ChatGPT plan |
| Driven by outside agents | MCP | MCP | MCP and a command line |
| Engine | Chromium | Gecko | WebKit |
| Tabs down the side | A setting | A setting | Yes |
| Spaces | Yes | No | Yes |
| Split View | Yes | Yes | Yes |
| Extensions | Chrome Web Store | Firefox add-ons | Chrome Web Store |
| Ad blocker | Built in | No | Built in |
| Open source | No | Yes | No |
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.
AIa matter of taste
Both have AI to ask about pages, and neither does the clicking for you. Opera AI answers about the page, Tab Islands, videos and files, and makes images, with no account; it doesn’t click or fill forms. 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 Codexeven
Opera can be driven over MCP, through Browser Connector, in early testing, which lets ChatGPT or Claude read and open tabs but not click or type. Firefox can be driven over MCP, through Mozilla’s Firefox DevTools MCP, which starts its own Firefox.
Tabs and windowsOpera leads
Opera has tabs down the side as a setting, spaces, Split View, folders in the sidebar and tabs that sleep. Firefox has tabs down the side as a setting, Split View, folders in the sidebar and tabs that sleep.
Priceeven
Opera: Free, with Opera AI and a browser VPN; VPN Pro is paid. Firefox: Free; its built-in VPN is free up to 50 GB a month.
Where it runseven
Both run on Mac, Windows, Linux, iPhone and Android. On a Mac, Firefox needs macOS 10.15 or later. On the phone, Opera: iPhone, iPad and Android; syncs tabs, bookmarks and Speed Dials with an Opera account. On the phone, Firefox: iPhone, iPad and Android; syncs tabs, bookmarks, passwords and history.
Engine and extensionsa matter of taste
Opera is built on Chromium, as Chrome is; Firefox on Gecko, Firefox’s engine. Opera takes extensions from the Chrome Web Store, Firefox from Firefox’s add-ons.
Privacyeven
Opera has an ad blocker built in and a VPN. Opera AI sends only the current page or Tab Island when you write with page access on; Opera says it doesn’t send your history. 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
- Opera AI only chats and sums up; agents need Opera Neon at $19.90 a month
- The free VPN covers the browser only, with three locations
- The ad blocker is off until you turn it on
- Browser Connector is in early testing and needs an Opera account
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
- July 23, 2026Opera: Vertical tabs shipped to all Opera One users
- April 16, 2026Opera: Browser Connector lets ChatGPT and Claude read your tabs over MCP (Early Bird)
- 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
- December 11, 2025Opera: Opera AI replaced Aria in Opera One, GX and Air
Questions
Is Opera free?
Yes. Free, with Opera AI and a browser VPN; VPN Pro is paid.
Is Firefox free?
Yes. Free; its built-in VPN is free up to 50 GB a month.
Which has an AI agent, Opera or Firefox?
Neither has an agent that does tasks in your pages. Opera AI answers about the page, Tab Islands, videos and files, and makes images, with no account; it doesn’t click or fill forms. 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 and Firefox run on Windows?
Yes, both. Opera runs on Mac, Windows, Linux, iPhone and Android; Firefox on Mac, Windows, Linux, iPhone and Android.
Do Opera and Firefox have phone apps?
Both do. On the phone, Opera: iPhone, iPad and Android; syncs tabs, bookmarks and Speed Dials with an Opera account. On the phone, Firefox: iPhone, iPad and Android; syncs tabs, bookmarks, passwords and history.
Can I move from Opera to Firefox?
Yes: Firefox’s own help says it brings in from Opera.
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; an agent that works in your signed-in tabs, 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 blog: Opera AI comes to Opera One, GX and Air
- Opera AI feature page
- Opera blog: Browser Connector
- Opera press: Browser Connector (2026-04-16)
- Opera blog: Opera 133 stable, vertical tabs (2026-07-23)
- Opera blog: how vertical tabs work
- Opera blog: Opera One R3
- Opera blog: new native ad blocker (2026-05-14)
- Opera free VPN page
- Opera Workspaces page (split screen, messengers)
- Opera Help: features (tab snoozing, messengers, workspaces)
- Opera Help: security and privacy (ad blocker, VPN)
- Opera Help: Password Manager
- Opera Help: import browsing data
- Opera Help FAQ: Chrome Web Store extensions
- Opera system requirements
- Opera Neon subscription
- Opera blog: Neon free plan for outside agents (2026-08-14)
- Opera blog: Opera One for iOS brings full synchronization (Jul 9, 2026)
- Opera: Sync your Opera browsers
- Opera: Flow / My Flow
- Opera Help (iOS): Connect your computer and phone with Flow
- Opera Browser with VPN on the App Store (iPhone and iPad)
- Opera: Private Web Browser on Google Play
- Mozilla blog: Smart Window
- Mozilla Support: get started with Smart Window
- Mozilla Support: model choices in Smart Window
- Smart Window privacy notice
- Firefox.com: Smart Window
- Mozilla blog: window types (2026-09-24)
- Mozilla blog: AI on your terms (AI controls)
- Firefox 148 release notes
- Firefox 149 release notes (split view, VPN)
- Mozilla blog: free built-in VPN
- Firefox 136 release notes (vertical tabs)
- Firefox 138 release notes (tab groups)
- Bugzilla 1730066: tab unloading enabled on macOS (Firefox 95)
- Firefox system requirements
- Firefox ESR 115 release notes (import sources)
- Firefox DevTools MCP (Mozilla)
- Firefox.com: Firefox browser sync
- Firefox on the App Store (iPhone and iPad)
- Firefox on Google Play
- Mozilla Support: Sync Firefox data
- Yab Manual: Bringing in from another browser
- Yab Manual: Connecting Claude or ChatGPT
- Yab Manual: Extensions
- Yab Manual: Yab’s tools over MCP
- Yab Manual: Privacy
Yab, Yet Another Browser.
Free for the Mac. Arc’s sidebar, your own Claude or ChatGPT as the agent, Chrome extensions on WebKit.