Internet Explorer 10 for the next version, Michael Muchmore of "PC Magazine" tested Platform Preview 1's performance and HTML5 support with both Microsoft's and third parties' test suites. In his test, Platform Preview 1 performed better than Internet Explorer 9 but not always better than the competing web browsers. On September 13, 2011, Microsoft released the developer preview of Windows 8 to general public, which came with Internet Explorer Developer Preview (the first full browser incarnation of Internet Explorer 10). Although Internet Explorer is the last major web browser – among Mozilla Firefox, Google Chrome, Opera, and Safari – to support spell checking,
Firefox page loads. In the final category, conformance, it was determined that Firefox had "strong" conformance for JavaScript and HTML5. In conclusion, "Tom's Hardware" determined that Firefox was the best browser for Windows 7 OS, but that it only narrowly beat Google Chrome. In June 2013, "Tom's Hardware" again performance tested Firefox 22, Chrome 27, Opera 12, and Internet Explorer 10. They found that Firefox slightly edged out the other browsers in their "performance" index, which examined wait times, JavaScript execution speed, HTML5/CSS3 rendering, and hardware acceleration performance. Firefox also scored the highest on the "non-performance" index, which measured memory efficiency,