Cross-browser, cross-platform, and cross-device compatibility testing ensuring consistent experience across environments. Use when validating browser support, testing responsive design, or ensuring platform compatibility.
Installation
Details
Usage
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skills listSkill Instructions
name: compatibility-testing description: "Cross-browser, cross-platform, and cross-device compatibility testing ensuring consistent experience across environments. Use when validating browser support, testing responsive design, or ensuring platform compatibility." category: specialized-testing priority: medium tokenEstimate: 800 agents: [qe-visual-tester, qe-test-executor, qe-performance-tester] implementation_status: optimized optimization_version: 1.0 last_optimized: 2025-12-02 dependencies: [] quick_reference_card: true tags: [compatibility, cross-browser, responsive, browserstack, playwright, devices]
Compatibility Testing
<default_to_action> When validating cross-browser/platform compatibility:
- DEFINE browser matrix (cover 95%+ of users)
- TEST responsive breakpoints (mobile, tablet, desktop)
- RUN in parallel across browsers/devices
- USE cloud services for device coverage (BrowserStack, Sauce Labs)
- COMPARE visual screenshots across platforms
Quick Compatibility Checklist:
- Chrome, Firefox, Safari, Edge (latest + N-1)
- Mobile Safari (iOS), Mobile Chrome (Android)
- Screen sizes: 320px, 768px, 1920px
- Test on actual target devices for critical flows
Critical Success Factors:
- Users access from 100+ browser/device combinations
- Test where users are, not where you develop
- Cloud testing reduces 10 hours to 15 minutes </default_to_action>
Quick Reference Card
When to Use
- Before release
- After CSS/layout changes
- Launching in new markets
- Responsive design validation
Browser Matrix
| Browser | Versions | Priority |
|---|---|---|
| Chrome | Latest, N-1 | High |
| Firefox | Latest, N-1 | High |
| Safari | Latest, N-1 | High |
| Edge | Latest | Medium |
| Mobile Safari | iOS latest | High |
| Mobile Chrome | Android latest | High |
Screen Breakpoints
| Category | Width Range |
|---|---|
| Mobile | 320px - 480px |
| Tablet | 481px - 768px |
| Desktop | 769px - 1920px+ |
Responsive Design Testing
import { test, expect } from '@playwright/test';
const devices = [
{ name: 'iPhone 12', width: 390, height: 844 },
{ name: 'iPad', width: 768, height: 1024 },
{ name: 'Desktop', width: 1920, height: 1080 }
];
for (const device of devices) {
test(`layout on ${device.name}`, async ({ page }) => {
await page.setViewportSize({
width: device.width,
height: device.height
});
await page.goto('https://example.com');
const nav = await page.locator('nav');
if (device.width < 768) {
// Mobile: hamburger menu
expect(await nav.locator('.hamburger')).toBeVisible();
} else {
// Desktop: full menu
expect(await nav.locator('.menu-items')).toBeVisible();
}
});
}
Cross-Browser with Playwright
// playwright.config.ts
import { defineConfig, devices } from '@playwright/test';
export default defineConfig({
projects: [
{ name: 'chromium', use: { ...devices['Desktop Chrome'] } },
{ name: 'firefox', use: { ...devices['Desktop Firefox'] } },
{ name: 'webkit', use: { ...devices['Desktop Safari'] } },
{ name: 'mobile-chrome', use: { ...devices['Pixel 5'] } },
{ name: 'mobile-safari', use: { ...devices['iPhone 12'] } }
]
});
// Run: npx playwright test --project=chromium --project=firefox
Cloud Testing Integration
// BrowserStack configuration
const capabilities = {
'browserName': 'Chrome',
'browser_version': '118.0',
'os': 'Windows',
'os_version': '11',
'browserstack.user': process.env.BROWSERSTACK_USER,
'browserstack.key': process.env.BROWSERSTACK_KEY
};
// Parallel execution across devices
const deviceMatrix = [
{ os: 'Windows', browser: 'Chrome' },
{ os: 'OS X', browser: 'Safari' },
{ os: 'Android', device: 'Samsung Galaxy S24' },
{ os: 'iOS', device: 'iPhone 15' }
];
Agent-Driven Compatibility Testing
// Cross-platform visual comparison
await Task("Compatibility Testing", {
url: 'https://example.com',
browsers: ['chrome', 'firefox', 'safari', 'edge'],
devices: ['desktop', 'tablet', 'mobile'],
platform: 'browserstack',
parallel: true
}, "qe-visual-tester");
// Returns:
// {
// combinations: 12, // 4 browsers × 3 devices
// passed: 11,
// differences: [{ browser: 'safari', device: 'mobile', diff: 0.02 }]
// }
Agent Coordination Hints
Memory Namespace
aqe/compatibility-testing/
├── browser-matrix/* - Browser/version configurations
├── device-matrix/* - Device configurations
├── visual-diffs/* - Cross-browser visual differences
└── reports/* - Compatibility reports
Fleet Coordination
const compatFleet = await FleetManager.coordinate({
strategy: 'compatibility-testing',
agents: [
'qe-visual-tester', // Visual comparison
'qe-test-executor', // Cross-browser execution
'qe-performance-tester' // Performance by platform
],
topology: 'parallel'
});
Related Skills
- mobile-testing - Mobile-specific testing
- visual-testing-advanced - Visual regression
- accessibility-testing - Cross-platform a11y
Remember
Test where users are, not where you develop. Developers use latest Chrome on high-end machines. Users access from older browsers, low-end devices, and slow networks.
Cover 95%+ of your user base. Use analytics to identify actual browser/device usage. Don't waste time on browsers nobody uses.
With Agents: Agents orchestrate parallel cross-browser testing across cloud platforms, reducing 10 hours of manual testing to 15 minutes. qe-visual-tester catches visual inconsistencies across platforms automatically.
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