That's an interesting use-case of web DRM.
There are other details in the article, for example about Recall forces users to use biometrics to then permit them to authenticate using a PIN code. That's an interesting observation.
All Signal does is just a simple Windows API call to exclude window from screen capture. SetWindowDisplayAffinity function with WDA_EXCLUDEFROMCAPTURE argument: https://learn.microsoft.com/en-us/windows/win32/api/winuser/...
https://learn.microsoft.com/en-us/windows/client-management/...
And that "simple Windows API" call is pretty much absolute, since it's across the stack.
any security hole on windows that enables an attacker to get to the recall db, would just as easily enable them to get to the signal db.
LorenDB•8mo ago