Source Code Viewer

A browser extension that replaces the browser's plain "View Source" with a readable, syntax-highlighted view — with multiple themes, word wrap, and clickable links. Built with WXT + TypeScript + Vue 3, and CodeMirror 6 for rendering.

Features

• Syntax Highlighting: Powered by CodeMirror 6, for HTML, CSS, JavaScript, JSON, and XML.
• Code Formatting: Automatic beautification of the source (via js-beautify).
• In-Place Auto-Open: Navigating directly to a raw .css/.js/.json/.xml URL renders the formatted viewer in place, keeping the original URL in the address bar.
• Multiple Themes: 45 CodeMirror themes (light & dark), loaded on demand, with a persistent selector.
• Word Wrap, Line Numbers & Folding: Toggle line wrapping; navigate with line numbers and code folding.
• Clickable Links: URLs in the source are clickable and routed by type — images open in the browser, other resources reopen in the viewer.
• Native Viewer Toggle: A toolbar button to open the browser's built-in view-source: viewer (same tab, or new tab with middle/Ctrl/Cmd-click).
• Smart Fallback: Detects restricted domains (like the Chrome Web Store) and falls back gracefully to the browser's native source viewer.
• Localized: Available in 9 languages (English, French, Spanish, German, Italian, Japanese, Simplified Chinese, and Brazilian/European Portuguese).
• Cross-Platform: Compatible with both Google Chrome and Mozilla Firefox (both Manifest V3).

Installation

Firefox

Visit the Firefox Add-ons page.

Chrome

Visit the Chrome Web Store page.

Development

Requires Node.js ≥ 24 and pnpm ≥ 11 (see packageManager in package.json).

pnpm install        # install dependencies
pnpm dev            # run in dev mode (Chrome); pnpm dev:firefox for Firefox
pnpm build          # build both chrome-mv3 and firefox-mv3 into .output/
pnpm zip            # produce the store zips (+ sources.zip)

Other useful scripts:

pnpm compile        # type-check (vue-tsc)
pnpm lint           # ESLint (type-aware)
pnpm lint:css       # Stylelint
pnpm format         # Prettier

License

Copyright (C) 2026 Nicolas Dos Santos

This project is licensed under the GNU General Public License v3.0 (or later) — see the LICENSE file for details.