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KeyframeEffectReadOnly.composite

This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The composite property of a KeyframeEffectReadOnly or a KeyframeEffect resolves how an element's animation impacts its underlying property values.

Note: For KeyframeEffect, this property is both a getter and a setter. For KeyframeEffectReadOnly, it is read-only.

// getting
var compositeEnumeration = keyframeEffect.composite;

// setting
keyframeEffect.composite = 'accumulate';

To understand these values, take the example of a keyframeEffect value of blur(2) working on an underlying property value of blur(3).

replace: The keyframeEffect overrides the underlying value it is combined with: blur(2) replaces blur(3).
add: The keyframeEffect is added to the underlying value with which it is combined (aka additive): blur(2) blur(3).
accumulate: The keyframeEffect is accumulated on to the underlying value: blur(5).

Specification	Status	Comment
Web Animations The definition of 'keyframeEffectReadOnly.composite' in that specification.	Working Draft	Editor's draft.

Feature	Chrome	Firefox (Gecko)	Internet Explorer	Opera	Safari (WebKit)
Basic support	No support	No support	No support	No support	No support

Feature	Android	Android Webview	Chrome for Android	Firefox Mobile (Gecko)	Firefox OS	IE Mobile	Opera Mobile	Safari Mobile
Basic support	?	?	?	?	?	?	?	?