SteamDB creator Pavel Djundik showed a screenshot of the feature on X (formerly Twitter), suggesting it’s currently in the works.
At the moment, if players have a game in their library that they may not want others to know about, they can choose to hide it from their library. All this does, however, is stop others seeing it in their list of games.
Once a player starts playing that game, their achievements and playtime for that will still be visible to others.
As such, at the moment the only way a player can truly ensure nobody knows they play a certain game is to set their entire Steam library, play activity and achievements to private.
The new feature will let players choose a specific game and select a “Mark as Private” option on its drop-down menu.