Steam Deck is getting a new feature called Steam Dynamic Cloud, and it makes it easier to transition between playing on the handheld to PC. With Steam Dynamic Cloud enabled, players don’t need to save and close the game on the handheld in order to open it on another client. Instead, even when players don’t exit the game, they can reopen the same title–with the most recent save–on their PC.
It’s just an extremely convenient way of switching between platforms without having to think about exits and saves. This feature won’t be automatically enabled for every game, as developers will have to implement this into their games for players to take advantage of it.
If developers don’t integrate Dynamic Cloud, Valve will still track player’ save game data within the cloud. However, the player will be prompted to save and exit their suspended game on the Steam Deck before being able to play the same title on PC.