---
name: chrome-fb01763edc64
slug: chrome
version: 1.0.0
description: Chrome DevTools Protocol, extension Manifest V3, and debugging patterns that prevent common automation failures.
homepage: https://clawic.com/skills/chrome
metadata:
  clawdbot:
    emoji: 🌐
    displayName: Chrome
---

## Chrome DevTools Protocol (CDP)

**Get tab WebSocket URL first**: Never connect to `ws://localhost:9222/devtools/browser` directly. Fetch `http://localhost:9222/json/list` and use `webSocketDebuggerUrl` from the active tab.

**Enable domains before use**: `Runtime.enable` and `Page.enable` must be called before any `Runtime.evaluate` or `Page.navigate` commands.

**CDP is async**: Wait for response before sending next command. Use Promise-based wrapper with response ID tracking.

**Screenshot on high-DPI**: Include `fromSurface: true` and `scale: 2` in `Page.captureScreenshot` params for Retina displays.

**Get response body separately**: `Network.responseReceived` doesn't include body. Call `Network.getResponseBody` with requestId after response completes.

## Chrome Extension Manifest V3

**Permissions split**: Use `permissions` for APIs, `host_permissions` for URLs. Never use `http://*/*` in permissions.

**Service workers terminate**: No persistent state. Use `chrome.storage.local` instead of global variables. Use `chrome.alarms` instead of `setInterval`.

**Content script isolation**: Can't access page globals. Use `chrome.scripting.executeScript` with `func` for page context. Use `window.postMessage` for content↔page communication.

**Storage is async**: `chrome.storage.local.get()` returns Promise, not data. Always await. Handle `QUOTA_EXCEEDED` errors.

## Context Detection

**Detect actual Chrome** (not Edge/Brave): Check `window.chrome && navigator.vendor === "Google Inc."` and exclude Opera/Edge.

**Extension context types**:
- `chrome.runtime.id` exists → content script
- `chrome.runtime.getManifest` exists → popup/background/options
- `chrome.loadTimes` exists but no runtime → regular Chrome web page

**Manifest version check**: Wrap `chrome.runtime.getManifest()` in try-catch. Use `chrome.action` for V3, `chrome.browserAction` for V2.

## Performance Debugging

**Memory API conditional**: Check `'memory' in performance` before accessing `performance.memory.usedJSHeapSize`.

**Use performance marks**: `performance.mark()` and `performance.measure()` for sub-frame timing. Clear marks to prevent memory leaks.

**Layout thrash detection**: PerformanceObserver with `entryTypes: ['measure', 'paint', 'largest-contentful-paint']`. Flag entries >16.67ms.

## Network Debugging

**Block before navigate**: Call `Network.setBlockedURLs` before `Page.navigate`, not after.

**Request interception**: Use `Network.setRequestInterception` with `requestStage: 'Request'` for granular control. Return `errorReason: 'BlockedByClient'` to block.

## Security Contexts

**Mixed content**: HTTPS pages can't load HTTP resources. Check `location.protocol` vs resource URL.

**CORS errors**: `TypeError` on cross-origin fetch usually means CORS. Check DevTools Network tab for specific error.

**Secure context required**: File System Access API, Clipboard API require `window.isSecureContext === true` and user gesture.


---
Source attribution: clawic
Original project: https://github.com/clawic/skills/blob/f825206afbf1c697202533a9187be68c7b697e0e/skills/chrome/SKILL.md
License: MIT
License information: https://opensource.org/license/mit
Original upstream instructions; downloaded from Mega AI Hub.

## Upstream license notice

MIT License

Copyright (c) 2026 Ivan G. Davila

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.



# Mega AI Hub resource metadata

Creator / publisher: clawic
Original project: https://github.com/clawic/skills/blob/f825206afbf1c697202533a9187be68c7b697e0e/skills/chrome/SKILL.md
Attribution basis: Source repository record

Fields of work: Development & Engineering, Product Management
Roles: Backend Developer, DevOps / SRE, Frontend Developer, Product Manager, QA / Test Engineer
Specialties: Backend, Frontend
Tools: Chrome Devtools
Country applicability: Country not specified
Classification basis: Source catalog labels
Instruction SHA-256: 5eafadeda9f7cb3ac2fb2453e0db3b13833f8b52b089dc11616a1776fa5e5670