NonSteamScraper has been released in version v1.5.2.

The tool does one-click artwork fetching (covers, hero images, logos) for your entire non-Steam game and app library from SteamGridDB.

This update is a safety release: the app should no longer lose or hide your artwork. Fixes include accidentally deleting another game’s artwork, the library being hidden after a rejected API key, and existing artwork being deleted when a download fails.

A safety release: the app no longer loses or hides your artwork.

• Selecting a game could delete another game’s artwork when their IDs overlapped in number. Now only the selected game’s art clears.
• When multiple SteamGridDB entries shared a name, the app could fetch the wrong artwork. The selection now persists accurately.
• A rejected API key no longer hides your library. Invalid keys now fail safely without moving games to Hidden.
• Failed downloads no longer delete existing artwork; replacements occur only after a successful download.
• Re-fetch and Undo are disabled during active fetches to prevent conflicts.
• Closing the window during a fetch now prompts for confirmation.
• Each Steam account gets its own shortcuts.vdf backup before modifications.
• Simultaneous file operations can no longer overwrite each other.
• Also fixed: preview mismatches, animated artwork timing, and single-instance enforcement.
• Performance: faster navigation and search in large libraries, lower CPU usage on the results screen.

Source: GitHub