open property
      
      bool
      get
      open
      
    
    
The open property of the
HTMLDetailsElement interface is a boolean value reflecting the
open
HTML attribute, indicating whether the details's contents (not counting
the summary) is to be shown to the user.
Implementation
external bool get open;
      
      set
      open
      (bool value) 
      
    
    
    
Implementation
external set open(bool value);