Web platform features explorer - 2D canvas opacity

Web platform features explorer

The optional alpha parameter of a 2D canvas's getContext() method sets whether the canvas has an alpha transparency channel. If set to false, then this permits the browser to optimize compositing for an opaque canvas.

Status

Limited availability

MDN documentation

HTMLCanvasElement: getContext() method

Specifications

HTML (#concept-canvas-alpha), from HTML Workstream (WHATWG).

Browser support

Chrome 32 Released on 2014-01-14
Chrome Android 32 Released on 2014-01-15
Edge 79 Released on 2020-01-15
Firefox 30 Released on 2014-06-10
Firefox for Android 30 Released on 2014-06-10
Safari ❌
Safari on iOS ❌

Baseline availability blocked since January 2020 by Safari (67 months)

Usage (according to Chrome Platform Status)

~42.348% of page loads. More data at chromestatus.

Web Platform Tests (WPT)

View the latest WPT test results for this feature

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