Non-standard
This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

The :-moz-window-inactive CSS pseudo-class is a Mozilla extension that matches any element while it's in an inactive window.

:-moz-window-inactive works in content HTML documents, too.

Note: Prior to the addition of this pseudo-class, giving different styles to background windows was achieved by setting an attribute (active="true") on the top-level XUL chrome window. This attribute is no longer used.

Example

This example alters the appearance of a box's background depending on whether its window is active or not.

HTML

<div id="mybox">
  <p>This is a box!</p>
</div>

CSS

#mybox {
  background: linear-gradient(to bottom, yellow, cyan);
  width: 200px;
  height: 200px;
}

#mybox:-moz-window-inactive {
  background: cyan;
}

Result

You can view this as a live sample here as well.

Specifications

Not part of any specification. This is a proprietary pseudo-class specific to Gecko.

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Basic support
Non-standard
Chrome No support NoEdge No support NoFirefox Full support 4IE No support NoOpera No support NoSafari No support NoWebView Android No support NoChrome Android No support NoEdge Mobile No support NoFirefox Android No support NoOpera Android No support NoSafari iOS No support NoSamsung Internet Android No support No

Legend

Full support  
Full support
No support  
No support
Non-standard. Expect poor cross-browser support.
Non-standard. Expect poor cross-browser support.

Document Tags and Contributors

Last updated by: fscholz,