Move the Mouse on Item 1 -> Item 1B -> Item 1B iii -> Submenu, then leave the Pane and quick reenter it before it close. Pane should stay open
Item 1
Item 1A
Item 1B
Item 1B i
Item 1B ii
Item 1B iii
Item 1B iii alpha
Item 1B iii omega
Item 1B iv
Item 1B iv alpha
Item 1C
Item 2
Item 2A
Item 2B
Item 3
Item 4