BetterTouchTool 5.560 alpha adds a new widget for floating menus: A navigable file / folder view. Here is an example preset that puts an expanding icon to the bottom left of the screen.
floating-folder2.bttpreset (17.4 KB)
Screenshots (optional)
@Andreas_Hegenberg would it be possible to have the file thumbnails come from qlmanage -t instead of the current generic thumbnails?