Microsoft is now ready to kill off Internet Explorer. The IE 11 desktop app will be retired on June 15, 2022, for most versions of Windows 10. Microsoft Edge still has a built-in Internet Explorer mode for websites that still need IE and those organizations that still use old apps and sites that don't work with modern browsers. The company plans to support Edge's IE mode until the end of 2029, giving these organizations a few more years to transition these old web apps.
Microsoft 365 and other apps will stop supporting IE 11 on August 17. The only versions of IE that won't be affected include the Windows 10 Long-Term Servicing Channel, which is used for devices that stay the same over time (like air traffic control systems and MRI machines), and the Server Internet Explorer 11 desktop applications or the MSHTML (Trident) engine.
Source: Engadget