The SELECT OTHER above the "select field" item will popout as I postion my cursor over it (at least for the first time)... the one below the "select field" item will not.
Confirmed. It's actually when the mouse touches the Select field, the sub-menus stop responding to hovers.
You can still click on them to open their menus, though.
(I'm actually surprised the Select field works at all in a menu as I think it was only designed to be used on the toolbar itself. )
so is this a bug or a feature .... you didn't say