Web/API/WindowOrWorkerGlobalScope

The WindowOrWorkerGlobalScope mixin describes several features common to the Window and WorkerGlobalScope interfaces. Each of these interfaces can, of course, add more features in addition to the ones listed below.

Note: WindowOrWorkerGlobalScope is a mixin and not an interface; you can't actually create an object of type WindowOrWorkerGlobalScope.

Properties

These properties are defined on the WindowOrWorkerGlobalScope mixin, and implemented by Window and WorkerGlobalScope.

WindowOrWorkerGlobalScope.caches Read only

Returns the CacheStorage object associated with the current context. This object enables functionality such as storing assets for offline use, and generating custom responses to requests.

WindowOrWorkerGlobalScope.crossOriginIsolated Read only

Returns a boolean value that indicates whether a SharedArrayBuffer can be sent via a Window.postMessage() call.

WindowOrWorkerGlobalScope.indexedDB Read only

Provides a mechanism for applications to asynchronously access capabilities of indexed databases; returns an IDBFactory object.

WindowOrWorkerGlobalScope.isSecureContext Read only

Returns a boolean indicating whether the current context is secure (true) or not (false).

WindowOrWorkerGlobalScope.origin Read only

Returns the origin of the global scope, serialized as a string.

Methods

These methods are defined on the WindowOrWorkerGlobalScope mixin, and implemented by Window and WorkerGlobalScope.

WindowOrWorkerGlobalScope.atob()

Decodes a string of data which has been encoded using base-64 encoding.

WindowOrWorkerGlobalScope.btoa()

Creates a base-64 encoded ASCII string from a string of binary data.

WindowOrWorkerGlobalScope.clearInterval()

Cancels the repeated execution set using WindowOrWorkerGlobalScope.setInterval().

WindowOrWorkerGlobalScope.clearTimeout()

Cancels the delayed execution set using WindowOrWorkerGlobalScope.setTimeout().

WindowOrWorkerGlobalScope.createImageBitmap()

Accepts a variety of different image sources, and returns a Promise which resolves to an ImageBitmap. Optionally the source is cropped to the rectangle of pixels originating at (sx, sy) with width sw, and height sh.

WindowOrWorkerGlobalScope.fetch()

Starts the process of fetching a resource from the network.

WindowOrWorkerGlobalScope.queueMicrotask()

Enqueues a microtask—a short function to be executed after execution of the JavaScript code completes and control isn't being returned to a JavaScript caller, but before handling callbacks and other tasks. This lets your code run without interfering with other, possibly higher priority, code, but before the browser runtime regains control, potentially depending upon the work you need to complete.

WindowOrWorkerGlobalScope.setInterval()

Schedules a function to execute every time a given number of milliseconds elapses.

WindowOrWorkerGlobalScope.setTimeout()

Schedules a function to execute in a given amount of time.

Specifications

Specification	Status	Comment
HTML Living StandardThe definition of 'WindowOrWorkerGlobalScope mixin' in that specification.	Living Standard	This is where the main mixin is defined.

Browser compatibility

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
WindowOrWorkerGlobalScope	Chrome Full support 4	Edge Full support 12	Firefox Full support 1	IE Full support Yes	Opera Full support Yes	Safari Full support Yes	WebView Android Full support Yes	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support Yes	Safari iOS Full support Yes	Samsung Internet Android Full support 1.0
atob	Chrome Full support 4	Edge Full support 12	Firefox Full support 1 Full support 1 Full support 27 Notes' Notes' atob() ignores all space characters in the argument to comply with the latest HTML5 spec (see bug 711180). Full support 57 Notes' Notes' atob() now defined on WindowOrWorkerGlobalScope mixin.	IE Full support 10	Opera Full support 10.5	Safari Full support 3	WebView Android Full support ≤37	Chrome Android Full support 18	Firefox Android Full support 4 Full support 4 Full support 27 Notes' Notes' atob() ignores all space characters in the argument to comply with the latest HTML5 spec (see bug 711180). Full support 57 Notes' Notes' atob() now defined on WindowOrWorkerGlobalScope mixin.	Opera Android Full support 11	Safari iOS Full support 1	Samsung Internet Android Full support 1.0
btoa	Chrome Full support 4	Edge Full support 12	Firefox Full support 1 Full support 1 Full support 52 Notes' Notes' btoa() now defined on WindowOrWorkerGlobalScope mixin.	IE Full support 10	Opera Full support 10.5	Safari Full support 3	WebView Android Full support ≤37	Chrome Android Full support 18	Firefox Android Full support 4 Full support 4 Full support 52 Notes' Notes' atob() now defined on WindowOrWorkerGlobalScope mixin.	Opera Android Full support 11	Safari iOS Full support 1	Samsung Internet Android Full support 1.0
caches Experimental'	Chrome Full support 40	Edge Full support ≤79	Firefox Full support 42 Full support 42 Full support 52 Notes' Notes' caches now defined on WindowOrWorkerGlobalScope mixin.	IE No support No	Opera ?	Safari No support No	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 42 Full support 42 Full support 52 Notes' Notes' caches now defined on WindowOrWorkerGlobalScope mixin.	Opera Android Full support Yes	Safari iOS Full support Yes	Samsung Internet Android Full support Yes
clearInterval	Chrome Full support 4	Edge Full support 12	Firefox Full support 1 Full support 1 Full support 52 Notes' Notes' clearInterval() now defined on WindowOrWorkerGlobalScope mixin.	IE Full support 4 Notes' Full support 4 Notes' Notes' From Internet Explorer 4 through 8, clearInterval is an Object rather than a Function. This behavior was fixed in Internet Explorer 9.	Opera Full support 4	Safari Full support 4	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4 Full support 4 Full support 52 Notes' Notes' clearInterval() now defined on WindowOrWorkerGlobalScope mixin.	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0
clearTimeout	Chrome Full support 45	Edge Full support 12	Firefox Full support 1 Full support 1 Full support 52 Notes' Notes' clearTimeout() now defined on WindowOrWorkerGlobalScope mixin.	IE Full support 4 Notes' Full support 4 Notes' Notes' From Internet Explorer 4 through 8, clearTimeout is an Object rather than a Function. This behavior was fixed in Internet Explorer 9.	Opera Full support 4	Safari Full support 4	WebView Android Full support 45	Chrome Android Full support 45	Firefox Android Full support 4 Full support 4 Full support 52 Notes' Notes' clearTimeout() now defined on WindowOrWorkerGlobalScope mixin.	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 5.0
createImageBitmap	Chrome Full support 50	Edge Full support 79	Firefox Full support 52 Notes' Full support 52 Notes' Notes' createImageBitmap() now defined on WindowOrWorkerGlobalScope mixin. Full support 42	IE No support No	Opera Full support Yes	Safari No support No	WebView Android Full support 50	Chrome Android Full support 50	Firefox Android Full support Yes	Opera Android Full support Yes	Safari iOS ?	Samsung Internet Android Full support 5.0
crossOriginIsolated Experimental'Non-standard'	Chrome No support No	Edge No support No	Firefox Full support 72	IE No support No	Opera No support No	Safari No support No	WebView Android No support No	Chrome Android No support No	Firefox Android No support No	Opera Android No support No	Safari iOS No support No	Samsung Internet Android No support No
fetch Experimental'	Chrome Full support 42	Edge Full support 14	Firefox Full support 39 Full support 39 Full support 34 Disabled' Disabled' From version 34: this feature is behind the dom.fetch.enable preference. To change preferences in Firefox, visit about:config. Full support 52 Notes' Notes' fetch() now defined on WindowOrWorkerGlobalScope mixin.	IE No support No	Opera Full support 29 Full support 29 Full support 28 Disabled' Disabled' From version 28: this feature is behind the Experimental Web Platform Features preference.	Safari Full support 10.1	WebView Android Full support 42	Chrome Android Full support 42	Firefox Android Full support 39 Full support 39 Full support 34 Disabled' Disabled' From version 34: this feature is behind the dom.fetch.enable preference. To change preferences in Firefox, visit about:config. Full support 52 Notes' Notes' fetch() now defined on WindowOrWorkerGlobalScope mixin.	Opera Android Full support 29 Full support 29 Full support 28 Disabled' Disabled' From version 28: this feature is behind the Experimental Web Platform Features preference.	Safari iOS Full support 10.3	Samsung Internet Android Full support 4.0
indexedDB	Chrome Full support 24	Edge Full support 12	Firefox Full support 16 Full support 16 Full support 10 Prefixed' Prefixed' Implemented with the vendor prefix: moz Full support 52 Notes' Notes' indexedDB now defined on WindowOrWorkerGlobalScope mixin.	IE Partial support 10	Opera Full support 15	Safari Full support 7	WebView Android Full support Yes	Chrome Android Full support 25	Firefox Android Full support 22 Full support 22 Full support 52 Notes' Notes' indexedDB now defined on WindowOrWorkerGlobalScope mixin.	Opera Android Full support 14	Safari iOS Full support 8	Samsung Internet Android Full support 2.0
isSecureContext Experimental'	Chrome Full support 55	Edge Full support ≤79	Firefox Full support 52	IE ?	Opera ?	Safari ?	WebView Android Full support 55	Chrome Android Full support 55	Firefox Android Full support 52	Opera Android ?	Safari iOS ?	Samsung Internet Android Full support 6.0
origin	Chrome Full support 59	Edge Full support ≤79	Firefox Full support 54	IE No support No	Opera No support No	Safari Full support 11	WebView Android Full support 59	Chrome Android Full support 59	Firefox Android Full support 54	Opera Android No support No	Safari iOS Full support 11	Samsung Internet Android Full support 7.0
queueMicrotask	Chrome Full support 71	Edge Full support 79	Firefox Full support 69	IE No support No	Opera Full support 58	Safari Full support 12.1	WebView Android Full support 71	Chrome Android Full support 71	Firefox Android No support No	Opera Android Full support 50	Safari iOS Full support 12.2	Samsung Internet Android Full support 10.0
setInterval	Chrome Full support 30	Edge Full support 12	Firefox Full support 1 Full support 1 Full support 52 Notes' Notes' setInterval now defined on WindowOrWorkerGlobalScope mixin.	IE Full support 4	Opera Full support 4	Safari Full support 1	WebView Android Full support 4.4	Chrome Android Full support 30	Firefox Android Full support 4 Full support 4 Full support 52 Notes' Notes' setInterval now defined on WindowOrWorkerGlobalScope mixin.	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 3.0
setTimeout	Chrome Full support 30	Edge Full support 12	Firefox Full support 1 Full support 1 Full support 52 Notes' Notes' setInterval now defined on WindowOrWorkerGlobalScope mixin.	IE Full support 4	Opera Full support 4	Safari Full support 1	WebView Android Full support 4.4	Chrome Android Full support 30	Firefox Android Full support 4 Full support 4 Full support 52 Notes' Notes' setInterval now defined on WindowOrWorkerGlobalScope mixin.	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 3.0

Legend

Full support  

Full support

Partial support  

Partial support

No support  

No support

Compatibility unknown  

Compatibility unknown

Experimental. Expect behavior to change in the future.'

Experimental. Expect behavior to change in the future.

Non-standard. Expect poor cross-browser support.'

Non-standard. Expect poor cross-browser support.

See implementation notes.'

See implementation notes.

User must explicitly enable this feature.'

User must explicitly enable this feature.

Requires a vendor prefix or different name for use.'

Requires a vendor prefix or different name for use.

See also

• Window
• WorkerGlobalScope

WindowOrWorkerGlobalScope by Mozilla Contributors is licensed under CC-BY-SA 2.5.