anchor.diff:            "Show a rendering of Markdown alongside the text."),
         new Menu("Reader", toolbar.readerHandler,
             "Show a full screen readonly view of the text.", true),
  -      new Menu(
  -          "Dark theme", toolbar.darkThemeHandler, "Switch app colours to a dark theme."),
  +      new Menu("Dark theme", toolbar.darkThemeHandler,
  +          "Switch app colours to a dark theme."),
         new Menu("Default theme", toolbar.defaultThemeHandler,
             "Switch app colours to the default theme."),
       ]);
   
       helpMenuItems.addAll([
         new Menu("About", toolbar.aboutHandler, "Find out more about NP8080."),
  -      new Menu("Manual", toolbar.manualHandler, "Read the NP8080 manual.", true),
  +      new Menu(
  +          "Manual", toolbar.manualHandler, "Read the NP8080 manual.", true),
         new Menu("What's New?", toolbar.whatsNewHandler,
             "Find out what's changed! - Hosted on Github.com.", true),
  -      new Menu("GitHub", toolbar.githubHandler, "Get the source code - Hosted on Github.com."),
  -      new Menu("Gitter Chat", toolbar.gitterHandler, "Gitter based Chatroom - Hosted on Gitter.com.")
  +      new Menu("GitHub", toolbar.githubHandler,
  +          "Get the source code - Hosted on Github.com."),
  +      new Menu("Gitter Chat", toolbar.gitterHandler,
  +          "Gitter based Chatroom - Hosted on Gitter.com.")
       ]);
   
       buildManual();
  
positive.code:       new Menu("Single Line", toolbar.oneLineHandler,
            "Put all the text onto one line.", true),
        new Menu("Reverse", toolbar.reverseHandler, "Reverse the line order."),
        new Menu("Randomise", toolbar.randomHandler, "Randomise the line order.", true),
        new Menu("Sort", toolbar.sortHandler, "Alphabetically sort lines."),
        new Menu("Number", toolbar.numberHandler, "Number non-blank lines.")
      ]);
  
negative.code:   final Function handler;
    final bool separator;
  
    Menu(this.name,
        [this.handler = null, this.tooltip = '', this.separator = false]);
  }
  
  class MenuDefinition {
  