Confirm the file is nonempty and retains the correct extension. Warp needs terminal_colors:, Alacritty TOML needs a colors table, and a Ghostty file must be extensionless with palette and background entries. Plist files must pass plutil -lint.
Check the destination shown in the preview, then restart the application. Terminal.app and iTerm2 imports still need selection in settings; Warp also needs selection in its theme UI. Alacritty and Ghostty require the configured theme name or path to match.
Alacritty YAML, multiple imports, and complex TOML structures are not rewritten automatically. Follow the path in the error, make a copy, and edit manually. The helper also refuses directories, symlink targets, and unsafe backup-manifest states.
Run bash bin/terminal-theme list-backups to verify the ID, then run restore without --yes to inspect its plan. If restore says a created file was later changed, do not force-delete it; compare the current file with the backup and decide manually which to retain.
Check whether the running program overrides ANSI colors, and distinguish terminal colors from editor themes, shell prompts, and fonts. Test in a new window; an existing window may retain old settings. A useful report includes macOS, terminal version, source URL, command, redacted output, and backup ID.