{"rewrite":{"id":"r_205435900d12c88df32ce66c","clusterId":"c_6b148267abcc4c488581876c","slug":"firefox-in-webassembly-runs-a-full-browser-inside-another-browser-tab","model":"deepseek-v4-flash","headline":"Firefox in WebAssembly Runs a Full Browser Inside Another Browser Tab","summary":"Puter Labs has released Firefox in WebAssembly, a project that compiles Mozilla Firefox's Gecko rendering engine and SpiderMonkey JavaScript engine to WebAssembly, allowing the browser to run entirely within another browser tab. The development used AI models extensively, with token costs exceeding $25,000 (about 4 million yen). The project is positioned as an experiment exploring WebAssembly limits, not a daily-use product.","whyItMatters":"The project demonstrates that a full browser engine can be ported to WebAssembly, but practical use remains limited by performance, network relay, and stability issues.","webCardHtml":"\u003cp\u003eThe project compiles Firefox\u0026#39;s Gecko rendering engine and SpiderMonkey JavaScript engine to WebAssembly using Emscripten. Network connections go through a Wisp relay server, so external sites see the relay\u0026#39;s IP address. GPU acceleration via WebGL is provided, and an experimental JIT compiler converts JavaScript to WebAssembly for speed. The developer said Firefox was chosen over Chromium because it has better mechanisms for running in a single process.\u003c/p\u003e\u003cp\u003eAI models including Claude Opus and Claude Fable were used for JIT compiler research and bug investigation, consuming about 30 billion tokens at a cost exceeding $25,000. The source code is available on GitHub and can be built on Linux. Input and scrolling do not work properly on smartphones, so the project is an experiment exploring WebAssembly limits, not a finished product for daily use.\u003c/p\u003e","blueskyPost":"Puter Labs released Firefox in WebAssembly, a full Firefox running inside a browser tab. It uses Gecko and SpiderMonkey compiled to WebAssembly. Development cost over $25k in AI tokens. An experiment, not for daily use.","twitterPost":"Puter Labs' Firefox in WebAssembly runs a full Firefox inside a browser tab. Gecko and SpiderMonkey compiled to WebAssembly. AI dev cost $25k+. Experimental, not production-ready.","threadsPost":null,"newsletterBlurb":"Puter Labs has released Firefox in WebAssembly, a project that compiles Mozilla Firefox's rendering and JavaScript engines to WebAssembly, allowing the browser to run entirely within another browser tab. The development used AI models extensively, costing over $25,000 in token usage. The project is an experiment exploring WebAssembly's limits, not a finished product for daily use.","attributionJson":"[{\"source\":\"GIGAZINE\",\"url\":\"https://gigazine.net/news/20260716-firefox-in-webassembly/\",\"title\":\"Firefox in WebAssembly lets you run Firefox entirely within a browser tab, with AI development costs totaling over 4 million yen\"}]","lintFlagsJson":null,"lintHits":0,"costUsd":0,"inputTokens":4227,"outputTokens":2302,"status":"published","repairAttempts":0,"nextRepairAt":null,"factsAttemptedAt":1784230288,"createdAt":"2026-07-16T19:25:27.000Z","publishedAt":"2026-07-16T19:27:28.000Z","updatedAt":"2026-07-16T19:25:27.000Z"},"cluster":{"id":"c_6b148267abcc4c488581876c","canonicalTitle":"Firefoxをブラウザのタブ内で丸ごと動かす「Firefox in WebAssembly」が登場、開発におけるAIコストは合計400万円以上に相当","representativeArticleId":"a_bc25a1a170a11c4e1d3951f2","sourceCount":1,"writtenSourceCount":1,"writeAttempts":0,"isSolo":true,"entitiesJson":"{\"anime_titles\":[],\"manga_titles\":[],\"work_titles\":[],\"studios\":[],\"people\":[],\"type\":\"news\",\"domain\":\"other\",\"is_roundup\":false}","contentType":"news","status":"published","firstSeenAt":"2026-07-16T07:00:00.000Z","lastSeenAt":"2026-07-16T07:00:00.000Z","updatedAt":"2026-07-16T19:27:29.000Z"},"attribution":[{"source":"GIGAZINE","url":"https://gigazine.net/news/20260716-firefox-in-webassembly/","title":"Firefoxをブラウザのタブ内で丸ごと動かす「Firefox in WebAssembly」が登場、開発におけるAIコストは合計400万円以上に相当"}],"entities":{"anime_titles":[],"manga_titles":[],"work_titles":[],"studios":[],"people":[],"type":"news","domain":"other","is_roundup":false},"keyFacts":null}