Sync html-externs e5a5a5b27b6.

std/js/html/webgl/RenderingContext.hx

@@ -325,7 +325,7 @@ extern class RenderingContext
 	static inline var UNPACK_COLORSPACE_CONVERSION_WEBGL : Int = 37443;
 	static inline var BROWSER_DEFAULT_WEBGL : Int = 37444;
 	
-	var canvas(default,null) : haxe.extern.EitherType<js.html.CanvasElement,Dynamic/*MISSING OffscreenCanvas*/>;
+	var canvas(default,null) : js.html.CanvasElement;
 	var drawingBufferWidth(default,null) : Int;
 	var drawingBufferHeight(default,null) : Int;