Firefox Smart Window: The browser that thinks before filling

Mozilla has updated Smart Window, Firefox's AI-powered browsing experience, with two features that go well beyond traditional autofill: smart form filling and page monitoring. The new capabilities, announced on Tuesday (October 27), use Google's Gemini 3.1 Flash Lite model to extract and suggest data from tabs the user has open — without ever submitting forms on their behalf.

The feature works as a cross-context assistant. If you have a job posting open in one tab and an application form in another, Smart Window can read the job description or your online portfolio and suggest tailored responses for each form field — not just your name and address, but written answers based on information from your open tabs. The interface appears when a form has at least four text fields, with a "Fill from sources" option in the dropdown menu. A pencil icon lets you edit or replace the source tabs.

Why this is different from the autofill you already use

Firefox's autofill has existed for years: it saves your basic details (name, address, email) and fills them instantly. Smart Window's difference is that it generates content, not just retrieves it. For an open-ended question like "Describe your experience in team management," the model can read your CV open in another tab and compose a coherent answer. This places Firefox in new territory: browsers that don't just display pages, but think about their content.

Mozilla emphasizes, however, that the AI doesn't submit anything. The user reviews every suggestion and confirms the filling. The model processes only the tabs you explicitly select — it doesn't scan your entire browsing history or access sensitive data like passwords or credit card numbers, which remain handled by local autofill.

The hidden side: sharing tabs with Google

Here's the point that deserves attention. When Smart Window fills a form, it sends the content of your selected tabs to Gemini 3.1 Flash Lite, Google's model. This means that when filling out a job application form, for instance, the content of your portfolio or LinkedIn page goes to Google's servers for processing.

Mozilla explains that Gemini 3.1 Flash Lite was chosen for offering "the best performance and reliability for this task." The chat model you choose for Smart Window (Claude, GPT-4, etc.) does not come into play — form filling uses exclusively Gemini, regardless of your preference. This is a detail that could friction with more privacy-sensitive users or those who use Firefox specifically to avoid the Google ecosystem.

Since 2022, Mozilla has had a strategic partnership with Google (which pays billions to be the default search engine), but integration with Google services has always been limited to search and YouTube. Using Gemini for user context processing opens a question that few browsers openly address: if the browser uses third-party AI to analyze your data, which third parties are actually analyzing it?

Page monitoring: the power of "watching without blinking"

The second feature is as useful as it is concerning. Smart Window can now monitor specific pages and notify you when an item you're watching changes price or when a new job listing appears on an employment portal. Each task can monitor up to five pages, and you can have up to fifteen active tasks. Checks happen daily or weekly — but require Firefox to be open.

This is essentially automated monitoring of web changes, performed from within the browser itself. There's no longer a need to use third-party services like Distill Web Monitor or PriceHubble. Firefox is becoming a personal surveillance agent — and the difference is that it runs locally, with direct user control over what to monitor.

Browsers as agents: the future

This update marks a conceptual shift. Browsers were designed to display content; Smart Window is designed to act on it. Intelligent form filling is a concrete step toward autonomous agents that don't just read pages, but interact with them — without submitting anything, without clicking for you, but with enough intelligence to understand what should go in each field.

Mozilla says it's already working on support for dropdown fields and PDF forms, along with mechanisms to save and manage AI-generated data for future use. If these features are implemented, Smart Window will move from being a convenience feature to becoming an autonomous productivity assistant within the browser.

The question isn't whether this convenience comes at a price that many Firefox users were willing to pay: handing the context of your tabs to Google's Gemini. Mozilla chose the best available model, certainly, but perhaps not the best for the trust of its most demanding users.

The Verge

The Verge covered the update with a balanced analysis, highlighting that Smart Window represents a natural evolution of the browsing experience: from a viewing tool to a contextual interaction tool.

Mozilla Blog

Mozilla's official publication provides complete technical details on the implementation, including the relationship between Smart Window and traditional autofill, as well as the support documentation explaining exactly how the AI processes tab data.

Unite.AI

Unite.AI brings a market perspective: Mozilla is positioning itself as the bridge between traditional browsing and the era of AI agents, with Smart Window being its boldest bet to date.

Sources: The Verge, Mozilla, Unite.AI, 9to5Mac

✓ Independent sources cross-checked and verified before publishing