In late 2023, Microsoft deprecated Microsoft Defender Application Guard for Office, and one month later, the same thing happened to Microsoft Defender Application Guard for Edge. Now, the company has updated the official list of deprecated Windows features with new details about MDAG deprecation and related apps and browser extensions.
Although the feature is called Microsoft Defender Application Guard for Edge, it offers browser extensions for Chrome and Firefox. The idea is to track untrusted websites and redirect them from your current browser to an isolated Microsoft Edge window so you can browse with fewer security risks.
Because Application Guard is deprecated there will not be a migration to Edge Manifest V3. The corresponding extensions and associated Windows Store app will not be available after May 2024. This affects the following browsers:
- Application Guard Extension - Chrome.
- Application Guard Extension - Firefox.
If you want to block unprotected browsers until you are ready to retire MDAG usage in your enterprise, we recommend using AppLocker policies or Microsoft Edge management service. For more information, see Microsoft Edge and Microsoft Defender Application Guard.
It is worth noting that the change mainly affects enterprise customers and not regular home users. Companies with existing installations of Microsoft Defender Application Guard can continue using it, but Microsoft recommends considering alternative options since MDAG "might be removed" from future Windows versions.
As for Manifest V3 extensions mentioned in the update, Microsoft initially planned to drop Manifest V2 in favor of V3 in January 2024. However, the company changed its plans, and the official documentation says that Microsoft is currently "in the process of updating our MV3 migration timelines."
Other recently deprecated features in Windows include Windows Subsystem for Android, Windows Mixed Reality, TLS certificates with short RSA keys, password payloads in MPR notifications, and others. To learn more, check out our comprehensive list of everything Microsoft discontinued in Windows in 2023.