Stardew Valley is a good example of why backing up a folder is safer than hunting for a single extension. A farm lives in its own directory, and the directory contains multiple related records. That makes the folder boundary the practical unit for backups. On Windows, macOS, and Linux the path is well documented and easy to copy once hidden application-data folders are visible. Before a major mod change or a manual save operation, copy the entire farm directory to a location outside the live Saves folder and give the copy a date.
Which storefront context matters
Documented Stardew Valley PC launchers/storefronts: Steam, GOG Galaxy, Xbox / Microsoft Store. The normal desktop save folder is shared by Windows builds that use the standard StardewValley application-data path, while Microsoft Store/Xbox packaging and cloud behavior can differ. Do not assume a console or mobile save can be copied directly into the desktop folder. The active storefront/account should be identified before any restore because cloud and local storage may not use the same path or container across editions.
Documented cloud behavior
Steam Cloud and GOG Galaxy cloud support are documented. Cloud sync is convenient but should not replace a dated offline copy before mods, save editing, or migration. Cloud synchronization is useful for continuity, but it can also turn a restore into a conflict-resolution event. Let synchronization settle before making a manual backup, and keep an offline copy outside any folder monitored by the launcher or operating-system sync service.
Local save roots still matter
The researched local save boundary is Windows: %APPDATA%StardewValleySaves | macOS: $HOME/.config/StardewValley/Saves/ | Linux / Steam Play: $XDG_CONFIG_HOME/StardewValley/Saves/ (normally ~/.config/StardewValley/Saves/); the known file or folder pattern is <FarmName>_<unique-id>
SaveGameInfo. A cloud-enabled game still has concrete local data involved in ordinary play, and that local context is what you need when identifying which copy was modified most recently.
Avoid accidental overwrite loops
Copy the whole farm folder, not only one file. This preserves the main save, SaveGameInfo, and any paired backup files that may be useful for recovery. When restoring, close the game and launcher, preserve both the current local copy and the backup you want to test, then place the intended data in the matching profile/storefront location. Do not repeatedly open the game between different copies without noting which side the cloud client selected.
Compatibility and conflict checks
Desktop saves are structured farm folders. Modded saves may depend on content or IDs provided by installed mods, so restoring the file without the same mod set can change behavior. If progress disappears or rolls back, If a farm disappears from the load menu, compare the folder name, the main save filename, and SaveGameInfo. Keep the original folder intact before trying older backup copies. Resolve identity/path/cloud questions first. A cloud conflict is not proof that the save itself is corrupt, and a successful upload is not proof that files from another storefront are compatible.
Verification context: Desktop save paths and cloud services were reviewed against current PCGamingWiki coverage. File-structure notes are limited to the standard farm-folder layout; no arbitrary XML rewrite is performed by this Game Hub.