Just a few weeks ago, a new "safe folder" feature was spotted in development for the Files by Google app, allowing you to move files into a PIN- or password-protected folder where they would be encrypted and inaccessible to other apps. Although the feature was never formally released to consumers, XDA Developers managed to get it working. Now, two weeks later, a warning message in the app states that the unreleased feature is "no longer supported."
I know, it's a little odd for Google to have implemented a warning dialog like this for a feature that was never publicly released and seemingly only made to work via manipulation of the app, but it's true. The change was spotted by XDA's Mishaal Rahman:
Well, this is strange. Google is already preparing to sunset....an unreleased feature in the Files by Google app. The feature is called "Safe Folder" and it lets you hide, ahem, your private files.
— Mishaal Rahman (@MishaalRahman) June 25, 2020
The new warning appears as a banner at the top of the screen when accessing the safe folder (which basically no one can do), explaining that the feature is "no longer supported." New files can't be moved into the safe folder, and files already present will be moved out or deleted at a future date. Note that you probably can't see this warning yourself because, again, it doesn't appear it was ever publicly enabled.
One possible explanation for warning that an unreleased feature is being disabled could have to do with Google's internal testing. The company has been known to test software features and changes internally in a practice that is called "dogfooding," and it's possible Googlers may have been using the safe folder feature themselves. Therefore, the warning might be for them.
Either way, it sounds like Google's Files app won't be getting the feature after all.