What about keeping the floating icon around even when onboard is visible? It could serve as a switch to show/hide onboard.
In fact, the tray icon and the floating icon serve similar (if not: identical) purposes. The floating icon is just way larger and easier to handle on a touch screen or under other circumstances which make exact pointing difficult. So I would suggest to add the hiding functionality to the floating icon and keep it visible.
What about keeping the floating icon around even when onboard is visible? It could serve as a switch to show/hide onboard.
In fact, the tray icon and the floating icon serve similar (if not: identical) purposes. The floating icon is just way larger and easier to handle on a touch screen or under other circumstances which make exact pointing difficult. So I would suggest to add the hiding functionality to the floating icon and keep it visible.