This feature was deprecated since it was found to break older versions of Mootools. Use Array.prototype.includes instead.

Where necessary, also adds the EventTarget methods addEventListener, removeEventListener and dispatchEvent.

A polyfill for the basic functionality of the Function.name accessor property in its pre-ES6 form.

This polyfilled Function.name accessor property can provide you with the name of a named function definition (either a named function declaration or a named function expression).

Unlike other browsers with a similar support level for the pre-ES6 form, this polyfilled name accessor property is also intentionally marked as configurable.

When polyfilling for Chrome <5, the accessor property will be both configurable (expected) AND enumerable (unexpected) due to having to implement it using Object.prototype.__defineGetter__ instead of Object.defineProperty.

Locales must be specified separately by prefixing the locale name with Intl.~locale, eg Intl.~locale.en-GB.

For compatibility with very old engines, Map.prototype.delete must be accessed using square bracket notation because 'delete' is a reserved word. myMap.delete() is an error in IE8. Use myMap['delete']() instead.

The test suite for this polyfill is derived from work of Andrea Giammarchi which is published under an MIT licence

In browsers that have no hooks to define getter functions (notably IE <= 8), attempting to defineProperty with a getter or setter function will fail. Since failing silently would likely break your application, we throw an exception. In IE8, this can be hard to diagnose because the console will just say 'Exception thrown and not caught'

In IE8, the catch & finally method cannot be invoked directly since they are reserved words. Instead, use ["catch"] and ["finally"] if intend to run your code in IE8

The Promise polyfill includes Promise.prototype.finally, to avoid needlessly serving this polyfill to those browsers, we have configured the browser targets for this polyfill to not include those configured in the Promise polyfill.

For compatibility with very old engines, Set.prototype.delete must be accessed using square bracket notation because 'delete' is a reserved word. mySet.delete() is an error in IE8. Use mySet['delete']() instead.

The test suite for this polyfill is derived from work of Andrea Giammarchi which is published under an MIT licence

This feature was deprecated since it was found to break older versions of Mootools. Use String.prototype.includes instead.

Polyfill requires Object getters so fails in IE < 8

Formerly supported by chrome and safari, but deprecated after discussion with Firebug. Use timeStamp() instead.

This polyfill just sets devicePixelRatio to 1 without attempting to measure it.

Older versions of Firefox are known to incorrectly alter the DPR on user zoom, but we don't (currently) correct for this

This polyfill will not work in IE11 because of a critical design choice made Microsoft ("Don't Call Me IE!") [1][2][3][4] in order to avoid consumers receiving an unnecessarily downgraded experience on websites that were making logic branch and feature decisions based on browser detection rather than feature detection.

The alias PageVisibility works for this feature for backwards compatibility with the name under which it was previously (erroneously) available

Makes use of FormData, FileReader and Blob if they exist. Readable streams not supported. CORS (Cross Origin Resource Sharing) requests do not work in IE 9 or lower.

In IE <= 8 window.screen is read-only, so the orientation property is not definable