Microsoft took to Twitter today to boast about Microsoft Edge achieving a 100% score on the HTML5 Accessibility test. However, while the performance of Chromium Edge is not in dispute, the metrics of the test may have been skewed in Microsoft’s favor.

If you’re unfamiliar with the HTML5 Accessibility test, it tests how browsers support HTML5 features through accessibility. For example, it shows how major browsers function with accessibility tools like screen readers:

“This site tests which new HTML5 features are accessibly supported by major browsers. This includes if they are keyboard accessible, mapped to the platform accessibility APIs, and if any accessibility related features are supported. An accessibly supported feature means it is usable by people who rely on assistive technology, without developers having to supplement with ARIA or other additional workarounds.”

Microsoft was clearly delighted with the result and celebrated it on Twitter. Browser market leader Google Chrome scored 92% and Edge’s nearest competitor Mozilla Firefox scored 89%. Apple’s Safaris was the closed to Microsoft Edge with 98%.

Skewed Test

However, Microsoft’s celebration may have been too soon. For some reason, the test was performed with version 80 of Edge, which is a new build. The test only used the aging Chrome 62 and Firefox 58. It is worth noting Chrome is now up to version 80 and Firefox is up to version 74.

It is unclear how the browsers would perform against Edge if newer version were used. However, it still would take away from the fact Edge scored a 100% score. For what it’s worth, Microsoft says it has nothing to do with which browser versions the HTML5Accesibility testers use.

You can see the test here.