Firefox Tomorrow

web api instance property

Screen: isExtended property

View on MDN ↗

Limited availabilitySecure context

The isExtended read-only property of the Screen interface returns true if the user’s device has multiple screens, and false if not.

This property is typically accessed via window.screen.isExtended, and can be used to test whether multiple screens are available before attempting to create a multi-window, multi-screen layout using the Window Management API.

Value

A boolean value — true if the device has multiple screens, and false if not.

[!NOTE] If a window-management Permissions-Policy is set that blocks use the Window Management API, isExtended will always return false.

Examples

if (window.screen.isExtended) {
  // Create multi-screen window layout
} else {
  // Create single-screen window layout
}

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also