#import 
#import 
#import 
typedef (CanvasRenderingContext2D or WebGLRenderingContext) RenderingContext;
// https://html.spec.whatwg.org/multipage/semantics.html#htmlcanvaselement
[Exposed=Window]
interface HTMLCanvasElement : HTMLElement {
    [HTMLConstructor] constructor();
    RenderingContext? getContext(DOMString contextId, optional any options = null);
    [CEReactions] attribute unsigned long width;
    [CEReactions] attribute unsigned long height;
    USVString toDataURL(optional DOMString type = "image/png", optional double quality);
};