Vector Markup Language MHT). Such files retain complete vector information, and can be reopened for editing using other Microsoft applications, such as Microsoft PowerPoint. VML was natively supported by Microsoft's Internet Explorer up to version 9 inline within HTML, using an undefined version of SGML namespaces. Support for VML was dropped in Internet Explorer 10 and subsequent versions. Support for "ink annotations" in Office Open XML files was added to LibreOffice during the 3.7 development cycle. VML is not natively supported by most web browsers. Web browsers such as Mozilla Firefox, Opera, Safari or Google Chrome support SVG instead of VML. Though VML
Firefox was created that loaded components of Firefox on startup, similar to Internet Explorer. A Windows Vista feature called SuperFetch performs a similar task of preloading Firefox if it is used often enough. Tests performed by "PC World" and Zimbra in 2006 indicated that Firefox 2 used less memory than Internet Explorer 7. Firefox 3 used less memory than Internet Explorer 7, Opera 9.50 Beta, Safari 3.1 Beta, and Firefox 2 in tests performed by Mozilla, CyberNet, and The Browser World. In mid-2009, BetaNews benchmarked Firefox 3.5 and declared that it performed "nearly ten times better on XP than Microsoft Internet