#7600 suggests that NVDA should work with Defender Application Guard (WDAG/MDAG) windows, however the current version produces no speech output when hovering elements or using NVDA-A to say all. As detailed below, I have narrowed this down to it working in 2019.2.1 and being broken from 2019.3 onwards.

Steps to reproduce:

1. Enable Application Guard through "Turn Windows features on or off", selecting "Microsoft Defender Application Guard", going through the necessary reboots, etc.
2. Start Edge
3. Access the "Settings and More" menu (ALT-F), "New Application Guard window"
4. In the newly appeared Edge window, navigate to http://nvaccess.org and attempt to read the page

Actual behavior:

NVDA remains silent.

Expected behavior:

Expect to hear page contents.

NVDA logs, crash dumps and other attachments:

nvda.log from 2023.1, enabled debug and UIA logging.

System configuration

NVDA installed/portable/running from source:

Tested both installed and running from the installer.

NVDA version:

2023.1.0.27913

Windows version:

Windows 10 22H2 19045.3208,
Windows 11 22H2 22621.1992

Name and version of other software in use when reproducing the issue:

Microsoft Edge 114.0.1823.86

Other information about your system:

These are two separate machines running different versions of Windows.

Other questions

Does the issue still occur after restarting your computer?

Yes

Have you tried any other versions of NVDA? If so, please report their behaviors.

Yes. The behaviour works with 2019.2.1 and breaks with 2019.3 onwards.

If NVDA add-ons are disabled, is your problem still occurring?

No add-ons are enabled.

Does the issue still occur after you run the COM Registration Fixing Tool in NVDA's tools menu?

Did not attempt this.