If you have files in subfolders and you want to view them all, or just quickly scan through contents you can do that by pressing Ctrl+B, or by clicking one of buttons:
There are other popular variants of this view mode:
Shift+Ctrl+B |
Show all enclosed files (for the current subfolder or selected) |
Alt+B |
Show all enclosed subfolders |
Shift+Alt+B |
Show all enclosed subfolders and files |
To cancel the enclosed view mode just go to another folder, press Backspace or press one more time Ctrl+B.