ctly after a number
    // without a space.
    properties.add(DoubleProperty(
      'device pixel ratio',
      ui.window.devicePixelRatio,
      tooltip: 'physical pixels per logical pixel',
    ));

    // Displaying the depth value would be distracting. Instead only display
    // if the depth value is missing.
    properties.add(ObjectFlagProperty&lt;int&gt;('depth', depth, ifNull: 'no depth'));

    // bool flag that is only shown when the value is true.
    properties.add(FlagProperty('using primary 