Possible null reference argument for parameter 'item' in 'void ShellView.SideMenuItemChanged(SideMenuItem item)'.

Possible null reference argument for parameter 'source' in 'IEnumerable<IItem> Enumerable.Cast<IItem>(IEnumerable source)'.

Non-nullable field '_items' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the field as nullable.

Non-nullable field '_listBox' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the field as nullable.

Possible null reference argument for parameter 'item' in 'bool AvaloniaList<Control>.Remove(Control item)'.

Converting null literal or possible null value to non-nullable type.

Possible null reference argument for parameter 'item' in 'bool AvaloniaList<Control>.Remove(Control item)'.

Converting null literal or possible null value to non-nullable type.

Cannot convert null literal to non-nullable reference type.