Browser Compatibility Tester

Table of Contents

Overview | Instructions (Local / Cloud) | Examples | Error Handling | Output | Resources

Overview

Test web applications across multiple browsers, rendering engines, and real devices. Validates CSS rendering, JavaScript API support, layout consistency, and interactive behavior across Chromium (Chrome, Edge), Gecko (Firefox), and WebKit (Safari) -- locally with Playwright or on real devices via BrowserStack, Sauce Labs, LambdaTest, or Kobiton.

Prerequisites

• Playwright installed (npx playwright install --with-deps) and application running at a test URL
• For cloud testing: provider credentials in environment variables (see ${CLAUDE_SKILL_DIR}/references/cloud-providers.md)

Instructions

Mode 1: Local Testing (Playwright)

Default mode. Zero cloud accounts needed.