Repository: files-community/Files
File: src/Files.App/Converters/Converters.cs (C#)

Code before:
		/// </summary>
		/// <param name="value"></param>
		/// <param name="parameter"></param>
		/// <param name="language"></param>
		/// <returns></returns>
		protected override Visibility Convert(object? value, object? parameter, string? language)
		{
			return value is null ? Visibility.Collapsed : Visibility.Visible;
		}

		/// <summary>
		/// Converts a target value back to the source type.
		/// </summary>
		/// <param name="value"></param>
		/// <param name="parameter"></param>
		/// <param name="language"></param>
		/// <returns></returns>
		protected override object? ConvertBack(Visibility value, object? parameter, string? language)
		{
			return new NotSupportedException();
		}
	}

	internal sealed partial class EmptyListToVisibilityConverter : ValueConverter<object?, Visibility>
	{
		/// <summary>
		/// Converts a source value to the target type.
		/// </summary>
		/// <param name="value"></param>
		/// <param name="parameter"></param>
		/// <param name="language"></param>
		/// <returns></returns>
		protected override Visibility Convert(object? value, object? parameter, string? language)
		{
			return (value is int count && count == 0) ? Visibility.Visible : Visibility.Collapsed;
		}

		/// <summary>
		/// Converts a target value back to the source type.
		/// </summary>
		/// <param name="value"></param>
		/// <param name="parameter"></param>
		/// <param name="language"></param>
		/// <returns></returns>
		protected override object? ConvertBack(Visibility value, object? parameter, string? language)
		{
			return new NotSupportedException();
		}
	}
}


Review comment (suggestion):
Instead of adding empty comments, simple `<inheritdoc/>` could be used (note that I didn't specify "cref" parameter)

Code after:
		/// </summary>
		/// <param name="value"></param>
		/// <param name="parameter"></param>
		/// <param name="language"></param>
		/// <returns></returns>
		protected override Visibility Convert(object? value, object? parameter, string? language)
		{
			return value is null ? Visibility.Collapsed : Visibility.Visible;
		}

		/// <summary>
		/// Converts a target value back to the source type.
		/// </summary>
		/// <param name="value"></param>
		/// <param name="parameter"></param>
		/// <param name="language"></param>
		/// <returns></returns>
		protected override object? ConvertBack(Visibility value, object? parameter, string? language)
		{
			return new NotSupportedException();
		}
	}

	internal sealed partial class EmptyListToVisibilityConverter : ValueConverter<object?, Visibility>
	{
		protected override Visibility Convert(object? value, object? parameter, string? language)
		{
			return (value is int count && count == 0) ? Visibility.Visible : Visibility.Collapsed;
		}

		protected override object? ConvertBack(Visibility value, object? parameter, string? language)
		{
			return new NotSupportedException();
		}
	}

	internal sealed partial class PopulatedListToVisibilityConverter : ValueConverter<object?, Visibility>
	{
		protected override Visibility Convert(object? value, object? parameter, string? language)
		{
			return (value is int count && count > 0) ? Visibility.Visible : Visibility.Collapsed;
		}

		protected override object? ConvertBack(Visibility value, object? parameter, string? language)
		{
			return new NotSupportedException();
		}
	}
}