Pierluigi Paganini
May 22, 2025
A Signal update for the Windows app prevents the system from capturing screenshots by default. The feature protects users’ privacy from Microsoft’s Recall feature.
“Signal Desktop now includes support for a new “Screen security” setting that is designed to help prevent your own computer from capturing screenshots of your Signal chats on Windows. This setting is automatically enabled by default in Signal Desktop on Windows 11.” reads the announcement published by Signal. “If you’re wondering why we’re only implementing this on Windows right now, it’s because the purpose of this setting is to protect your Signal messages from Microsoft Recall.”
The feature announced by Microsoft” Copilot+ PCs in 2024 captures screenshots of the user’s laptop every few seconds.
“You can use Recall on Copilot+ PCs to find the content you have viewed on your device. Recall is currently in preview status; during this phase, we will collect customer feedback, develop more controls for enterprise customers to manage and govern Recall data, and improve the overall experience for users.” reads the announcement.
Microsoft explained that the Recall feature will store encrypted snapshots locally on the user’s computer, the feature will be only implemented in forthcoming Copilot+ PCs. Microsoft doesn’t have access to the snapshot.
Privacy advocates expressed their concerns about the potential abuses of the feature.
The IT giant attempted to downplay the risks for the users, it pointed out that the feature was developed with privacy and security by design and it is an “optional experience.”
Microsoft added that Recall does not take snapshots of certain kinds of content, such as InPrivate web browsing sessions in Microsoft Edge.
Users can manage which snapshots Recall collects, excluding specific apps or websites. They can also pause snapshot collection, clear some or all stored snapshots, or delete all snapshots from their device.
The company suspended the rollout of the features following the public concerns, but recently started testing it again.
“Although Microsoft made several adjustments over the past twelve months in response to critical feedback, the revamped version of Recall still places any content that’s displayed within privacy-preserving apps like Signal at risk.” continues Signal. “As a result, we are enabling an extra layer of protection by default on Windows 11 in order to help maintain the security of Signal Desktop on that platform even though it introduces some usability trade-offs. Microsoft has simply given us no other option.”
Signal’s new screen security blocks screenshots, showing only a blank screen. Unfortunately, it may affect some accessibility software, including screen readers or magnification tools for people who are visually impaired. Users can disable it via settings, with a warning and confirmation to avoid accidental deactivation.
Signal said that when you are trying to take a screenshot with the new screen security setting enabled, you will just get a blank screen.
Signal’s screen security on Windows 11 is easy to disable, but the developers say it is hard to turn off accidentally, requiring a warning and confirmation. The setting only applies locally and doesn’t affect screenshots or accessibility tools on other devices like macOS or Linux.
“We hope that the AI teams building systems like Recall will think through these implications more carefully in the future. Apps like Signal shouldn’t have to implement “one weird trick” in order to maintain the privacy and integrity of their services without proper developer tools. People who care about privacy shouldn’t be forced to sacrifice accessibility upon the altar of AI aspirations either.” concludes the announcement.
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