# NotebookLM Code Highlighter > Adds beautiful syntax highlighting for code blocks in Google NotebookLM. Features auto language detection, 6 color themes, line numbers, and one-click copy Canonical page: [https://chrome-stats.com/d/notebooklm-code-highlighter](https://chrome-stats.com/d/notebooklm-code-highlighter) ## Overview - **ID:** `notebooklm-code-highlighter` - **Platform:** Firefox - **Type:** Firefox add-on - **Status:** Available - **Publisher:** Alex - **Category:** appearance - **Daily users:** 6 - **Version:** 1.0.0 - **Last updated:** 2026-01-28 - **First published:** 2026-01-25 - **Size:** 4.90 MB - **Data as of:** 2026-09-06 - **Store listing:** [Firefox Add-ons Store](https://addons.mozilla.org/firefox/addon/notebooklm-code-highlighter/) - **Website:** [https://koval.xyz](https://koval.xyz/) ## Description NotebookLM Code Highlighter transforms plain code blocks in Google NotebookLM into beautifully formatted, syntax-highlighted snippets. FEATURES • Automatic language detection for 25+ programming languages • 6 color themes: GitHub, VS Code, and Atom One (light & dark variants) • Line numbers for easy reference • One-click copy button • Respects your system's light/dark mode preference • Adjustable max height for long code blocks SUPPORTED LANGUAGES JavaScript, TypeScript, Python, Java, C, C++, C#, Go, Rust, Ruby, PHP, Swift, Kotlin, SQL, Bash, Shell, JSON, XML, HTML, CSS, SCSS, Markdown, YAML, Dockerfile, GraphQL, and Plain Text. HOW IT WORKS The extension automatically detects code blocks on notebooklm.google.com and applies syntax highlighting in real-time. You can manually override the detected language using the language picker, and your preference is remembered for that code block. PRIVACY This extension runs entirely in your browser. It does not collect, store, or transmit any user data. No analytics, no tracking, no ads. OPEN SOURCE View the source code and report issues on GitHub. ## Rankings - #42,117 — Overall - #41 — notebook - #102 — highlighter - #223 — code ## Permissions and access ### Permissions - `storage` - `https://notebooklm.google.com/*` ### Content script matches - `localhost` - `notebooklm.google.com` ## Safety - **Risk impact:** Moderate risk impact - **Risk likelihood:** Moderate risk likelihood ### Analysis details - Request access to the following domains: google.com, localhost - This extension has low user count. Unpopular extensions may not be stable or safe. > Some risk analysis details are omitted from this free response. [Upgrade to view the full analysis](https://chrome-stats.com/pricing). ## Similar extensions and apps - [Notion Syntax Highlighter](https://chrome-stats.com/d/notion-syntax-highlighter) — 1 users - [Raw Code Highlighter](https://chrome-stats.com/d/raw-code-highlighter) — 1 users - [Syntax Highlighter](https://chrome-stats.com/d/syntax-highlighter) - [Code Highlighter](https://chrome-stats.com/d/code-highlighter) — 1 users, 5.00 / 5 - [GML Syntax Highlighter](https://chrome-stats.com/d/gml-syntax-highlighter) — 4 users, 5.00 / 5 - [Code Highlighter](https://chrome-stats.com/d/code_highlighter) — 16 users, 5.00 / 5 - [Code Highlighter](https://chrome-stats.com/d/codehighlighter) — 24 users, 5.00 / 5 - [Code Snippet Highlighter](https://chrome-stats.com/d/code_snippet_highlighter) — 20 users, 5.00 / 5 - [Go Docs Syntax Highlighter](https://chrome-stats.com/d/go-docs-syntax-highlighter) — 5.00 / 5 - [Code Formatter](https://chrome-stats.com/d/web-code-formatter) — 25 users, 5.00 / 5 - [Enlight](https://chrome-stats.com/d/enlight) — 247 users, 4.65 / 5 - [Godocs Highlighter](https://chrome-stats.com/d/godoc-highlighter) --- Source: [Chrome-Stats](https://chrome-stats.com/d/notebooklm-code-highlighter)