AI Limitations & FAQ
Web Highlights has no AI server. AI summaries, AI chat and AI flashcards run on the language model that is built into your browser — Google's Gemini Nano in Chrome, Microsoft's Phi-4-mini in Edge. That is what keeps your pages, highlights and notes on your own device (why our AI is privacy-first). It also means the AI can only run where the browser ships a model. This page lists those limits.
Which browsers and operating systems can run the AI features?
Each browser ships its own model on its own list of operating systems:
| Browser | Model | Windows 10/11 | macOS | Linux | Android / iOS / ChromeOS |
|---|---|---|---|---|---|
| Google Chrome 138+ | Gemini Nano | ✅ | ✅ 13+ (Ventura) | ✅ | ❌ |
| Microsoft Edge (recent) | Phi-4-mini | ✅ | ✅ 13.3+ | ❌ No model — the AI cannot run on Edge/Linux | ❌ |
| Brave, Arc, Vivaldi, Opera, other Chromium | none yet | ❌ | ❌ | ❌ | ❌ |
| Firefox, Safari | none | ❌ | ❌ | ❌ | ❌ |
Where a browser has no model, the AI buttons stay hidden or disabled with a hint — highlighting, notes, tags, collections and everything else keep working. The extension checks the browser's own availability API, so support appears automatically once a browser ships a model.
Sources: Chrome built-in AI requirements · Microsoft Edge Prompt API requirements
I use Edge on Linux and the AI is stuck on Setting up AI
This is a platform limit, not a broken install. Microsoft ships Edge's on-device model only for Windows 10/11 and macOS 13.3+. Edge for Linux does not include the model and cannot download it, so there is nothing for the extension to initialize.
Edge for Linux still exposes the AI interface to extensions, which is why Web Highlights can get stuck on "Setting up AI…" — it is waiting for a model download that never starts. We know this state is confusing and should say so plainly.
What works on Linux today is Chrome (Gemini Nano runs on Linux). Two ways to use that:
- Use Chrome for Web Highlights — install the extension there and everything, including the AI features, works in one place.
- Keep Edge for reading and highlighting and open Chrome only for the AI: summaries, chat and flashcard generation all work in the web app. Your highlights get there via cloud sync, so this needs an account (sync is free for the first 7 days and part of the paid plans after that).
If Chrome then has trouble downloading the model, the Chrome AI troubleshooting guide covers the usual fixes.
Why is there no cloud fallback when my browser has no model?
Because sending your pages to a server is exactly what the on-device design avoids. Most AI features ship the page you are reading and your notes to a cloud service to be processed and stored. Web Highlights does not — your content is processed by the model inside your own browser and is never uploaded for AI, not even to us. You can verify that in your browser's DevTools network tab.
The trade-off is that the AI only runs where the browser provides a model. If you want AI on a browser that has none yet, vote for it on the feature board — that is how we see which browsers matter most.
What hardware does the on-device model need?
- Chrome: about 22 GB of free disk space on the volume with your Chrome profile before the download starts (that is headroom, not the model size — the model is about 3–4 GB), plus a GPU with more than 4 GB VRAM or, without a capable GPU, 16 GB RAM and at least 4 CPU cores. If free space later drops below 10 GB, Chrome removes the model.
- Edge (Windows/macOS): at least 20 GB free on the profile volume, a GPU with 5.5 GB VRAM or more, and an unmetered connection — Edge does not download the model on a metered connection.
The download happens once, the first time you use an AI feature, and the browser manages it. Keep the browser open until it finishes; a restart is sometimes needed afterwards. Progress is visible at chrome://on-device-internals/ (Chrome) or edge://on-device-internals/ (Edge) under "Model Status".
Do the AI features work on every page?
No. Browsers expose the built-in AI only on secure (https://) pages. On a plain http:// page the model is not available even in a fully set-up browser — open the page over https:// or use the web app, which always runs on a secure page. Details in the troubleshooting guide.
Which languages can the AI write?
- AI summaries follow the language of the page, or the language you pick in the summary's menu — the on-device summarizer writes English, German, Spanish, French and Japanese. Pages in other languages are summarized in their own language when possible.
- AI chat answers in the language you use Web Highlights in.
- AI flashcards stay in the language of the highlight.
There is no global AI-language setting yet — vote for it here.
Is the AI free?
The free plan includes a small daily allowance of AI actions — one AI summary, one AI chat and one generated flashcard deck per day. The paid plans lift those limits. See the pricing page for the full comparison.
Still stuck?
- Work through the Chrome AI troubleshooting guide — flags, model status, download problems.
- Check that your browser and operating system are on the supported list above.
- Still no luck? Email marius@web-highlights.com with your browser, version and operating system — that is usually all it takes to find the cause.