Linux Launcher Cannot Open Folder (Failed to show URI:file:)

What the log looks like

java\.io\.IOException: Failed to show URI:file:

How to fix it

1. To access your files right away without the button, open your Linux file manager manually, press Ctrl+H to show hidden folders, and navigate to `~/.var/app/com.atlauncher.ATLauncher/data/` (for Flatpak) or `~/.local/share/atlauncher/` (for native packages).
2. If you installed ATLauncher via Flatpak, install `xdg-desktop-portal` along with the portal backend for your desktop environment (such as `xdg-desktop-portal-gtk` or `xdg-desktop-portal-kde`) on your host system, then restart your session.
3. If you are running ATLauncher through Lutris, install ATLauncher natively instead (via Flatpak, AUR `atlauncher-bin`, `.deb`/`.rpm`, or the standalone `.jar`), as Lutris injects custom library paths that prevent host file managers from launching.
4. If you use a minimal window manager (such as i3, Sway, or Hyprland), ensure `xdg-utils` and `gvfs` are installed and assign a default file manager by running `xdg-mime default <file-manager>.desktop inode/directory` in a terminal.
5. Update ATLauncher to the latest version, as newer releases include improved fallback commands (`xdg-open`) for Linux desktop environments when Java's built-in `Desktop.open` fails.

Check your own log