Microsoft is urging users to update to the latest version of Internet Explorer after it discovered a serious flaw. For one, it allows users to switch quickly between apps. Typically, after several months, Microsoft changes the label to simply "Semi-Annual Channel" (SAC) and announces that the feature upgrade has been sufficiently tested - again, mainly by consumers - to make it suitable for deployment in businesses and organizations.
Microsoft is giving you a new place to try out software from unknown sources. Since this preview is from the 19H1 branch, it will come out during the first half of next year, similarly like the previous preview build.
It'll also be available for download in the Microsoft Store and starting in summer 2019, will ship with new Windows 10 devices. That's a good thing, because hackers can easily access the user's computer with the vulnerability.
For Windows 7, Vista and XP, however, Internet Explorer is more visible. Microsoft will leave your current Start menu layout alone "because [they] want everything to be exactly as you left it before you did the update". "The new layout has been simplified into a sleek one column design with reduced top-level tiles".
Microsoft describes features of upcoming Windows Sandbox - Software - News
Microsoft is introducing a new feature called Windows Sandbox that will allow you to safely run executables in a throw-away virtualized sandbox without fear of your regular Windows install becoming infected. The objective of the new Sandbox is, as you might expect, to provide "an isolated, temporary, desktop environment where you can run untrusted software without the fear of lasting impact to your PC".
So even if you don't use IE 11 - or any Microsoft browser - bits of it are lurking on every Windows system, presumably in case any older Microsoft applications or websites need to use them. We love the new Windows Sandbox feature, which will let you safely run Windows applications without worrying about malware or junk files that will get scattered across your system.
It is not known if your installed applications on the host OS will also be available in the Windows Sandbox.