transactionToUndo property
      
      Transaction?
      get
      transactionToUndo
      
    
    
This read-only property returns the Transaction in the #history to be undone next. The value may be null if the UndoManager is not ready to perform an undo.
Implementation
_i3.Transaction? get transactionToUndo => _i4.getProperty(
      this,
      'transactionToUndo',
    );
      
      set
      transactionToUndo
      (Transaction? value) 
      
    
    
    
Implementation
set transactionToUndo(_i3.Transaction? value) {
  _i4.setProperty(
    this,
    'transactionToUndo',
    value ?? _i5.undefined,
  );
}