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A minimal viable browser: what changed in v1.1.0
From v1.0.0 (2026-10-18, de821285d) to v1.1.0 (2026-10-18, e9fbb78e9), paragraph by paragraph.
0 paragraphs added, 0 removed, 7 changed in place, 58 unchanged. About 42 words added and 5 removed. Insertions are marked like this, deletions like this; unchanged runs are folded to one line; figures appear as their file names.
15 unchanged paragraphs, under In short {#in-short}, The biggest program we run {#biggest}
The cost of that shows up in the bug counts. In May, Mozilla wrote that it fixed 423 security bugs in Firefox in April 2026, against roughly 20 to 30 a month through 2025. 271 of them were found with an Anthropic model and fixed in Firefox 150: 180 rated high, 80 moderate, 11 low. ManyA number of them were sandbox escapes, written assuming the content process was already compromised and going after the privileged parent process through IPC, IndexedDB and image decoding. Chrome is seeing the same: one update on 6 October 2026 fixed 247 vulnerabilities. Counted from NVD by the organisation that filed them, Google's Chrome team filed 202 CVEs in 2025 and 3,246 in 2026 up to 17 October; Mozilla's filed 213 and 675 (Mozilla's also cover Thunderbird and other products). This is the code you do not ship argument at its largest: models now find what was always there, and every feature in the engine is a place to look.
7 unchanged paragraphs, under What a minimal viable browser looks like {#shape}
Firefox has had pieces of this, and dropped some of them. It had a site-specific browser, behind a hidden preference, and removed it in Firefox 8686](https://bugzilla.mozilla.org/show_bug.cgi?id=1682593) in 2021, citingciting known bugs and weak user research. It has a kiosk mode, started with --kiosk. It has had site isolation on for every desktop user since Firefox 95, which is the process boundary a component model needs. And Servo, the engine Mozilla started in Rust, is now an embeddable library, published as 0.1.0 in April 2026 under Linux Foundation Europe.
2 unchanged paragraphs, under A browser for one agent {#agent}
The vendors say plainly that this will not be fixed. OpenAI wrote in December 2025 that prompt injection, "much like scams and social engineering on the web, is unlikely to ever be fully 'solved'" (TechCrunch). GoogleGoogle's callsChrome indirectsecurity promptteam injectionwrote in December 2025 that "the primary new threat facing all agentic browsers".browsers is indirect prompt injection"](https://blog.google/security/architecting-security-for-agentic/). Gartner told most organisations to block AI browsers for now.
5 unchanged paragraphs, under Every extension in its own box {#extensions}
The pattern in the incidents is not malicious code at install. It is a trusted extension that changes. Koi's ShadyPandaShadyPanda reportreport, as The Hacker News relayed it, covers 145 extensions with about 4.3 million installs,installs across 145 extensions (20 for Chrome and 125 for Edge, Koi's count of one phase), some of them "Featured" or "Verified", that were legitimate for years and then were weaponised through auto-update. Urban VPN Proxy, with a Featured badge, began harvesting every prompt and reply on ChatGPT, Claude, Gemini and Copilot from a July 2025 update, with no off switch. Firefox is not immune: Koi's later DarkSpectre attribution includes Firefox add-ons.
18 unchanged paragraphs, under Parts of this exist {#exists}, Why Mozilla {#why-mozilla}, Sell it as speed {#speed}
The pitch to Mozilla should not be security. Security has neverrarely been enough to make people switch browsers, and Firefox at 2.8% of the market in September 2026 knows that better than anyone.it.
8 unchanged paragraphs, under What this does not claim {#limits}
• Mozilla's 2024 and 2025 revenue split is from interviews and its ledger page. Its latestledger page links its 2024 audited statements on its site are for 2023.statements.
3 unchanged paragraphs, under Where this comes from {#sources}
A voice memo from me on 18 October 2026. The research, read on 18 October 2026: Mozilla, hardening Firefox, 7 May 2026; state of Mozilla 2025/26 and its blog post, 27 January 2026; AI controls; Smart Window, 18 August 2026; Manifest V3 update, 13 March 2024; data collection consent, 23 October 2025; Project Fission; MediaNama, interview with Mark Surman, 4 April 2026; StatCounter, browser market share, September 2026; Servo, 0.1.0, 13 April 2026; Microsoft, browse safer with Edge, and The Record on the 2021 JIT figure; GrapheneOS, features; Apple, Lockdown Mode; OpenAI's statement as reported by TechCrunch, 22 December 2025; BleepingComputerGoogle, onarchitecting [Chrome'ssecurity agentfor security;agentic capabilities in Chrome](https://blog.google/security/architecting-security-for-agentic/), 8 December 2025; Brave, AI browsing and unseeable prompt injections, 21 October 2025; Zenity Labs, PleaseFix, 3 March 2026; Dark Reading, zero-click agent hijacking, August 2026; The Register, Gartner on AI browsers, 8 December 2025, and Urban VPN, 16 December 2025; LayerX, extension security report 2025; Koi,The ShadyPanda;Hacker News on Koi's ShadyPanda report, December 2025; Cybernews, DarkSpectre; Privacy Guides, Brave Origin, 7 June 2026; Malwarebytes, Chrome update, October 2026; Thurrott on Firefox 85; Lightpanda, repository; Chrome, headless shell; Tauri, start; NVD, CVE counts by source identifier. Related: the code you do not ship, what can your agent reach, cloudflare as Lego blocks, the value of constraints. Written up and checked by this site's agent; the editorial responsibility is mine.