A weekly roundup of the frontend and AI-in-frontend news worth your time.
Developers can finally use Gemini 4 Argon! Meta's Muse Wonder Full came third on Artificial Analysis' Intelligence Index. Claude Haiku 5.5 and Firefox 158 are out. Then there's Core Web Vitals for single-page apps, browser news, more decision models, Intelligent UI in ChatGPT, Genkit Dart 1.0, and Vercel's storage charges.
A lot happened this week. I became a Google Developer Expert in Web Technologies! Gemini 4 Argon tied GPT-6 Astra and Claude Fable 5.1. Chrome 155 and Firefox 158 are out. Then there's what's coming in Chrome 156 and 157, more decision models, Pi 1.0, news from Antigravity and Claude Code, OpenAI's text watermarks, and Cloudflare's AI toll.
TOCus is officially out! In AI news, Google announced Gemini 4 Argon, OpenAI had a big DevDay where they announced GPT-6.1 Sol and some bad news for current Pro users, and Anthropic released Claude Sonnet 5.5. Then there's Firefox 157, CSS corner shapes, an open model that finds browser bugs, vertical wrap in Figma, Gemini's text-to-speech models, and JavaScript iterators.
Claude Opus 5.5 led Artificial Analysis' tests. I explain what Jev is, the thing everybody is talking about. OpenAI released GPT-6 Sol and Luna, SpaceXAI introduced Grok 4.7, and Xiaomi's MiMo-V2.6-Pro is now free. Chrome 154 allows embedded frames to resize to fit the page, Lighthouse 13.5 checks support for AI assistants, and Cloudflare added previews for each branch. Google, Anthropic, and OpenAI updated their programming tools, and nine mathematicians will help OpenAI with sharing math research.
Apple put a sale date on its first foldable iPhone, so screens that fold in half are about to get a lot more common. Google's live voice models went generally available, Firefox changed a scrollbar check that may unhide styles you wrote, OpenAI deleted the line about training on the mathematicians' drafts, Safari 27 reached phones, tablets, and laptops, and Tailwind Labs is joining Shopify.
Artificial Analysis swapped the tests behind the model table so every score moved, Chrome 153 shipped camera and microphone as real HTML elements, OpenAI launched GPT-6 Astra and published an AI-written Navier-Stokes proof, Claude, ChatGPT, and Grok broke on the same morning, and NVIDIA signed to buy Hugging Face.
Claude Fable 5.1 took the top of the model table, Gemini 3.8 Flash came in as the fastest model on it, Chrome and Firefox both shipped, OpenAI is cutting Cursor off, and Go, Flutter, and Dart join The Brief.
OpenAI made its best model cheaper, Stripe is buying OpenRouter, an Amazon for AI models, and Mozilla cleared the way for JPEG XL.
Five models entered the weekly table at once, GitHub lost most of a Monday, and Firefox 154 finished two CSS features the other engines already had.
Anthropic explains the invisible watermark Claude will leave in text it generates, Meta ships the Muse Code terminal agent and opens Muse Glimmer's weights, and the State of CSS 2026 results show what other developers actually ship. Plus a refreshed ARIA in HTML rulebook, 41 Chrome security fixes, and two new rows in the model table.
