Browser Compatibility & Web Hardware APIs
Engine differences across Chromium, Gecko, WebKit, and hardware API availability.
Browser compatibility refers to how consistently different web browser engines (Blink in Chrome/Edge, Gecko in Firefox, WebKit in Safari) implement modern Web APIs for graphics, media, touch, and hardware sensors.
Why It Matters
A test that works seamlessly in Google Chrome on Windows (such as vibration or gamepad access) may be intentionally unsupported in Apple Safari on iOS due to platform security policies and privacy sandboxing.
What Users Should Look For
- Vibration API (`navigator.vibrate`) not functioning on desktop browsers or iOS Safari
- Motion sensor events requiring explicit permission taps on iOS Safari but running automatically on Android Chrome
- Fullscreen API behaving differently on mobile phones versus desktop monitors
- Color gamut negotiation differing between macOS Safari (Display P3) and Windows Chrome
How to Test This Parameter
- 1Open the Browser Compatibility tool in Screen Tester to inspect support status across 16 core Web APIs
- 2Review the compatibility status table for your specific active browser and operating system
- 3Test hardware features on alternate browsers (such as Firefox or Edge) if an API is unavailable
Technical Testing Boundaries & Methodology
Screen Tester emphasizes transparency: we clearly delineate between what web browser engines can mathematically inspect versus what requires specialized physical laboratory probes.
- ✓Feature detection of global API objects in the `window` and `navigator` namespaces
- ✓Support flags for Web Audio, WebRTC, Pointer Events, Fullscreen, Vibration, and Motion APIs
- ✓User agent and browser engine characteristics for diagnostic compatibility grouping
- ✕Unreleased or experimental browser flag toggles (`chrome://flags` or `about:config`)
- ✕Operating-system level firewall or enterprise group policy restrictions
- ✕Third-party privacy extension script blocking behavior
API Support Across Major Engines
Chromium (Google Chrome, Microsoft Edge, Brave): Broadest hardware API implementation, including Vibration API, Screen Wake Lock, and Fullscreen API.
Gecko (Mozilla Firefox): Strong standards compliance, excellent canvas rendering and Web Audio support, conservative hardware sensor implementation.
WebKit (Apple Safari): Strict privacy sandboxing, requires explicit user gestures for sensors, omits Vibration API, but provides leading Color Management and Display P3 wide gamut support on Apple displays.
Common Causes
- •Safari / WebKit policy omitting non-standard hardware APIs (like Web Vibration API) for privacy reasons
- •Accessing a website over unencrypted HTTP: modern browsers disable camera, microphone, and motion APIs on non-HTTPS origins
- •Strict browser tracking protection or privacy extensions blocking sensor event listeners
- •Running an outdated browser version lacking modern WebRTC or Canvas 2D color space extensions
Recommended Next Steps
- →Keep your web browser updated to the latest stable release
- →Always connect via secure HTTPS to ensure all modern browser Web APIs are unlocked
- →Use Chrome or Edge on Android when testing physical vibration and haptic feedback
Frequently Asked Questions
Why doesn't the Vibration Test vibrate my iPhone?
Apple has intentionally never implemented the Web Vibration API in WebKit/Safari to prevent web advertisements and spam sites from triggering intrusive device haptics. Physical vibration testing requires an Android device running Chrome or Firefox.
Do I need to install any browser extensions to use Screen Tester?
No. Screen Tester is 100% zero-install and client-side. It operates entirely on native standard W3C Web APIs supported natively by modern web browsers.