<!doctype html> <meta charset="utf-8"> <title>WebGLRenderingContext attributes test</title> <script> var canvas = document.createElement('canvas'), gl = canvas.getContext('webgl'); if ( gl.canvas !== canvas ) console.error("Expected a canvas getter"); if ( typeof gl.drawingBufferWidth !== "number" || typeof gl.drawingBufferHeight !== "number" ) console.error("drawingBuffer{Height/Width} should be numbers"); </script>