Ferry sends to the device you pick: one of your phones or another computer, from the pill in Ferry's menu. Only that device gets it. Another computer gets it straight away, and Send Clipboard puts it on that computer's clipboard.
Ferry's menu and phone page are new: what arrived on one card, and Aa (a text), Send Clipboard and + (files) below it. Drag files over the menu to drop them on a device. Add Device is in the pill's list.
Undo for windows:⌘⇧U opens the window you closed with ⌘W again, where it was.
File pickers open floating in the middle of the screen.