The WebContextEvent interface is part of the WebGL API and is an interface for an event that is generated in response to a status change to the WebGL rendering context.


This interface inherits properties and methods from its parent interface, Event.


This interface inherits properties from its parent interface, Event.

A read-only property containing additional information about the event.


This interface doesn't define any own methods, but inherits methods from its parent interface, Event.


With the help of the WEBGL_lose_context extension, you can simulate the webglcontextlost and webglcontextrestored events:

var canvas = document.getElementById('canvas');
var gl = canvas.getContext('webgl');

canvas.addEventListener('webglcontextlost', function(e) {
}, false);


// WebGLContextEvent event with type "webglcontextlost" is logged.


Specification Status Comment
WebGL 1.0
The definition of 'WebGLContextEvent' in that specification.
Recommendation Initial definition.

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support9124911125.1
Available in workers No No491 No No No
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support Yes25 Yes49128.1 Yes
Available in workers No No No No No No No
statusMessage Yes25 Yes49128.1 Yes

1. From version 49: this feature is behind the gfx.offscreencanvas.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.

See also

Document Tags and Contributors

Contributors to this page: fscholz, nmve, teoli
Last updated by: fscholz,