René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Check for actual MathML rendering","articleBody":"The HTML5 test checks that the browser correctly parses inline SVG and MathML, but does not actually verify that any attempt at actually rendering the content is made. Even if this is clearly annotated on the test, it would be appropriate to check that in addition to just parsing the tags, the user agent actually makes at least an effort at rendering.\r\n\r\nFor MathML,  something like this can be used:\r\n\r\n```javascript\r\nfunction hasMathMLSupport() {\r\n        var div = document.createElement(\"div\"), box;\r\n        div.innerHTML = \"\u003cmath\u003e\u003cmspace height='23px' width='77px'/\u003e\u003c/math\u003e\";\r\n        document.body.appendChild(div);\r\n        box = div.firstChild.firstChild.getBoundingClientRect();\r\n        document.body.removeChild(div);\r\n        var has = Math.abs(box.height - 23) \u003c= 1  \u0026\u0026 Math.abs(box.width - 77) \u003c= 1;\r\n        return has;\r\n}\r\n```\r\n\r\n(adapted from [here](https://github.com/fred-wang/mathml.css/blob/master/mspace.js).)\r\n","author":{"url":"https://github.com/Oblomov","@type":"Person","name":"Oblomov"},"datePublished":"2017-08-11T16:41:52.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/511/HTML5test/issues/511"}