Get a lost window back

Work through these in order:

1. Check the message. If a window moved, a message on screen says where it went.
2. Check the overflow row. Look for a strip at the bottom edge and press ⌃⌥↓.
3. ⌘Tab to the app. JimiOS takes you to the workspace holding the window, or shows the overflow row.
4. Check the other workspaces. Press ⌥1 to ⌥9 in turn.
5. Quit JimiOS from its menu. Quitting puts every window back on screen. Then open it again.