Compatibility Testing

This one automates cross-browser and cross-device testing, running your tests in parallel across Chrome, Firefox, Safari, and Edge, plus mobile viewports. It uses Playwright for local testing and integrates with BrowserStack or Sauce Labs when you need real devices. The qe-visual-tester agent catches visual differences across platforms automatically. Use it before releases, after layout changes, or when validating responsive design. The real value is cutting 10 hours of manual cross-browser checking down to 15 minutes of parallel execution. Focus your matrix on the browsers your analytics show people actually use, not every possible combination.

skills.sh installs: 654
GitHub stars: 524
last updated: Aug 21, 2026

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Install

$ npx -y skills add proffesor-for-testing/agentic-qe --skill compatibility-testing --agent claude-code

Installs into .claude/skills of the current project.

Files

Compatibility Testing

Browser engine

Browser-driven checks (viewport emulation, responsive validation, cross-browser screenshots) should go through the qe-browser fleet skill (.claude/skills/qe-browser/). Vibium is installed by aqe init. Quick reference:

# Viewport emulation per breakpoint
vibium viewport 375 667   # mobile
vibium viewport 768 1024  # tablet
vibium viewport 1920 1080 # desktop

# Full device emulation (user-agent, DPR, touch)
vibium emulate-device "iPhone 15"

# Visual diff per viewport
for vp in "375 667 mobile" "768 1024 tablet" "1920 1080 desktop"; do
  read w h name <<< "$vp"
  vibium viewport $w $h
  node .claude/skills/qe-browser/scripts/visual-diff.js --name "homepage-$name"
done

Cross-browser (Firefox/Safari) still requires Playwright or a cloud device farm today — Vibium's BiDi backend is Chrome-only at v26.3.x.

SKILL.md on GitHub