Internet Explorer mode for Edge

Context

What is IE mode?
IE mode on Microsoft Edge makes it easy to use all of the sites your organization needs in a single browser. It uses the integrated Chromium engine for modern sites, and it uses the Trident MSHTML engine from Internet Explorer 11 (IE11) for legacy sites.

When a site loads in IE mode, the IE logo indicator displays on the left side of navigation bar.

Only those sites that you specifically configure (via policy) will use IE mode, all other sites will be rendered as modern web sites. For a site to use IE mode, you need to either:

List the site in the Enterprise Mode Site List XML defined in one of these policies:
Microsoft Edge 78 or later, "Configure the Enterprise Mode Site List"
Internet Explorer, "Use the Enterprise Mode IE website list"

More information, including minimum requirements for the Windows Operating System and Microsoft Edge version: https://docs.microsoft.com/en-us/deployedge/edge-ie-mode