By Steven Hawley
Signal, the secure communications app that encrypts all of its communication in the name of privacy, announced that it has added what it calls a new “screen security” feature, to block the Recall feature in Windows 11 from automatically taking screenshots.
Microsoft’s rationale for Recall is “to enable you to quickly find and jump back into what you have seen before on your PC. You can use an explorable timeline to find the content you remember seeing before” – to act as a “photographic memory.”
Backlash was quick to come, which resulted in Microsoft pulling the feature from availability.
Microsoft responds
Microsoft reintroduced Recall in April with encryption and making it an opt-in feature. Now, Microsoft says that “To use Recall you need to opt in to saving snapshots, which are … saved and encrypted to your local hard drive. Recall does not share snapshots or associated data with Microsoft or third parties, nor is it shared between different Windows users on the same device.”
In an un-dated post, Microsoft also describes filtering features that are positioned as privacy enhancements. Snapshots also won’t be saved when supported remote desktop clients are used.
Typical to PC culture, the user interface is complicated and the documentation for these safety features is many pages long; likely above the comprehension levels of most non-developers.
Not infallible
Signal noted that if the user attempts to take a screenshot of Signal Desktop when screen security is enabled, nothing will appear. With one caveat: as long as a “WDA_EXCLUDEFROM CAPTURE” DRM flag is set by the software developer.
They warned that “(The DRM Flag) setting is local to your computer and doesn’t apply to screenshots on other devices. Also, if you are communicating with someone who uses a screen reader on macOS or Linux, keeping screen security enabled on your side won’t prevent them from taking screenshots or adversely affect any accessibility software they may be using.”
Furthermore, when Microsoft re-introduced Recall in April, Ars Technica warned that “Even if User A never opts in to Recall, they have no control over the setting on the machines of Users B through Z. That means anything User A sends them will be screenshotted, processed with optical character recognition and Copilot AI, and then stored in an indexed database on the other users’ devices. That would indiscriminately hoover up all kinds of User A’s sensitive material, including photos, passwords, medical conditions, and encrypted videos and messages.”
Signal sets this blocking feature “on” by default, but, like Recall, Signal’s blocking feature can be disabled.
Further reading
By default, Signal doesn’t Recall. Blog post. May 21, 2025. Signal
Retrace your steps with Recall. Support page. Accessed May 29, 2025. Microsoft Corporation
Microsoft will switch off Recall by default after security backlash. Article. June 7, 2024. by Andy Greenberg. Wired
That groan you hear is users’ reaction to Recall going back into Windows. Article. April 11, 2025. by Dan Goodin. Ars Technica
Japan: Defendants referred for producing and posting movie summaries online without permission. Article. May 22, 2025. by Steven Hawley. Piracy Monitor
Why it matters
Recall is positioned as an AI-enabled aid that helps users maintain an audit trail of their work, which can be useful simply for recalling a workflow, or, for gathering evidence.
But critics were quick to say how Recall could enable least several use-cases that might give pause. While Signal doesn’t explicitly put it this way, there seems to be nothing preventing Recall from taking screenshots of copyrighted content which a user can distribute at will. For example, in a recent case, Japanese plaintiffs sued a defendant for combining unlicensed images with the defendant’s own descriptions.
So in that light, Signal’s blocking feature is a plus for rights-holders.
Recall also raised multiple red flags around privacy issues. One that immediately comes to mind is how corporate IT departments have long been tasked to monitor worker activity. Recall gives them another tool. So from that perspective, if Microsoft enabled enterprise developers to over-ride the user controls from Recall, an employer attempted to use Recall in a jurisdiction where such monitoring is regulated, Signal could provide a safeguard.
