ProxyLoom

ProxyLoom is a Manifest V3 browser extension for explicit, deterministic HTTP and HTTPS proxy routing. One WXT/Vue/TypeScript codebase produces a Chromium package for Chrome, Chromium, Edge, and Yandex Browser, plus a Firefox MV3 package.

Routing model

Mode	Rule evaluation	No matching rule
DIRECT	Rules and temporary overrides are ignored	Direct
PROXY	Temporary override → first matching rule	Selected global proxy
RULES	Temporary override → first matching rule	Direct

An assigned proxy is fail-closed: ProxyLoom never appends a hidden DIRECT, system-proxy, or second-proxy fallback. Recovery requires an explicit user action.

Origin Rules are portable. Full URL Rules, including path and query, run only in Firefox and are kept visible but skipped in Chromium. HTTP/WS targets use the HTTP endpoint; HTTPS/WSS targets use the HTTPS endpoint.

Features

• separate HTTP and HTTPS proxy endpoints, including proxy authentication;
• globally ordered first-match rules with an explicit direct or proxy-profile route, domain-suffix templates plus editable Russian-sites and social-network examples, search, filters, drag-and-drop and keyboard ordering;
• local regex and full routing testers with no network requests;
• Once/Always site actions and private-session isolation;
• redacted local routing logs and a best-effort main-frame error page;
• inactive-profile checks through the selected proxy, only after an explicit click;
• native JSON merge/replace/export and profiles-only FoxyProxy 6–9 import;
• system/light/dark themes and localized English UI;
• local-only storage, no analytics, telemetry, accounts, ads, remote config, or remote code.

Screenshots

Development

Requirements: Node 22 or newer and pnpm 10.32.1.

pnpm install --frozen-lockfile
pnpm dev
pnpm dev:firefox

Production builds:

pnpm build
pnpm build:firefox
pnpm zip
pnpm zip:firefox
pnpm package:artifacts

Install unpacked Chromium output from .output/chrome-mv3. Firefox development uses pnpm dev:firefox; release candidates are generated in .output.

Verification

pnpm check
pnpm test:coverage
pnpm test:performance
pnpm test:soak
pnpm test:integration
pnpm test:e2e
pnpm audit
pnpm run licenses
pnpm build
pnpm build:firefox
pnpm validate:build
pnpm scan:artifacts
pnpm zip
pnpm zip:firefox
pnpm package:artifacts
pnpm validate:packages
pnpm validate:source-rebuild
(cd .output && sha256sum ProxyLoom-*.zip > SHA256SUMS)
(cd .output && sha256sum --check SHA256SUMS)

All network integration uses loopback origin/proxy fixtures. The Firefox API gate temporarily installs MV3 test extensions through WebDriver BiDi. Separate headed smokes exercised the final product builds in official Firefox 153 Stable, Google Chrome 150 Stable, Microsoft Edge 150 Stable and Yandex Browser 26 Stable. Firefox and Edge include real private routing, memory-only log isolation and DIRECT restoration; Firefox also includes an MV3 idle-wake check. See the browser evidence and architecture decisions.

Privacy and browser limits

Credentials are stored in ordinary extension local storage; this is not an encrypted vault. Default exports omit credential keys. Persistent logs contain hostname and scheme, never path, query, headers, bodies, cookies, or credentials. Private logs remain in memory.

Chromium Once overrides are origin-scoped and may affect other tabs on the same site until the source tab closes. Firefox can apply reliable tab-scoped overrides. Error-page navigation is best effort. Read Privacy, the User Guide, and Known Limitations.

Store publication and the full signed Chrome/Firefox/Edge/Yandex matrices are intentionally human release steps; no workflow contains store credentials or publishing actions.

Firefox reviewers can reproduce the submitted package by following SOURCE_CODE_REVIEW.md. The release gate rebuilds the extension from the source ZIP and compares every generated file digest with the tested Firefox output.