Previous discussion of same topic: <a href="https://news.ycombinator.com/item?id=44053364">https://news.ycombinator.com/item?id=44053364</a>
In short: Signal uses DRM to prevent Windows Recall (spyware) from capturing what's inside the app. It's similar to how Netflix prevents piracy.<p>That's an interesting use-case of web DRM.<p>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.
and as plenty of people have noted, virtue signaling. As signal already saves one's entire chat history by default in an easily digestible db.<p>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.