When you start the legacy version of Microsoft Edge, you receive a notification stating support of this version ended on March 9, 2021. After March 9, 2021, the Microsoft Edge Legacy desktop application will not receive new security updates.
To suppress the deprecation notification for the Microsoft Edge Legacy application, change the "Suppress the display of Edge Deprecation Notification" group policy setting to Enabled. For more information about the SuppressEdgeDeprecationNotification policy, see the Browser/SuppressEdgeDeprecationNotification topic of the Policy configuration service provider on the Microsoft Learn website.
For more information about the end of support for Microsoft Edge Legacy, see the following articles:
For information about the end of support for all Microsoft products, see here.