# Mozilla Used Mythos to Fix 271 Firefox Bugs

**URL:** https://discuss.privacyguides.net/t/mozilla-used-mythos-to-fix-271-firefox-bugs/37360
**Category:** News
**Created:** 2026-04-22T22:00:15Z
**Posts:** 5

## Post 1 by @nateb — 2026-04-22T22:00:15Z

Mozilla has [announced](https://www.wired.com/story/mozilla-used-anthropics-mythos-to-find-271-bugs-in-firefox/) that Firefox 150 (set to be released this week) will include fixes for 271 bugs found using Anthropic's "Claude Mythos" AI.

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This is a companion discussion topic for the original entry at [https://www.privacyguides.org/news/2026/04/22/mozilla-used-mythos-to-fix-271-firefox-bugs](https://www.privacyguides.org/news/2026/04/22/mozilla-used-mythos-to-fix-271-firefox-bugs)

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## Post 2 by @DanielM — 2026-04-22T22:57:40Z

![code-28](https://forum-uploads.privacyguidesusercontent.com/original/3X/3/6/363d911f68c5560cd49417feed0886f2717680b4.jpeg)→ **Joel Weinberger using Claude from Anthropic** ([Source oficial](https://www.mozilla.org/en-US/security/advisories/mfsa2026-30/))

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## Post 3 by @hashcatHitman — 2026-04-23T03:13:17Z

I think it might be (the whole list of people) using Claude rather than (the last guy) using Claude, since I know Alex Gaynor actually works at Anthropic.

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## Post 4 by @Expert4870 — 2026-04-23T04:26:30Z

Hopefully one of them is this bug.

https://-fingerprint-com/blog/firefox-tor-indexeddb-privacy-vulnerability/

> **[We Found a Stable Firefox Identifier Linking All Your Private Tor Identities](https://web.archive.org/web/20260422190706/https://fingerprint.com/blog/firefox-tor-indexeddb-privacy-vulnerability/)**
>
> We discovered a privacy vulnerability in Firefox Private Browsing and Tor Browser that allows websites to fingerprint and track users across origins using IndexedDB database ordering, even after closing all private windows.

> We found a stable Firefox identifier linking all your private Tor identities

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## Post 5 by @hashcatHitman — 2026-04-23T04:46:30Z

That was already fixed and is expected in Firefox 150, as the article mentions.

The fix is here: [Bug 2024220 - IDB database must return a sorted list. r=dom-storage-r… · mozilla-firefox/firefox@2c28194 · GitHub](https://github.com/mozilla-firefox/firefox/commit/2c2819428c57eae022f02b53825364a4b1963872)