Examine source code of Halloween Jack Night ...

{
  "theme": {
    "images": {
      "theme_frame": "trick3.jpg"
    },
    "colors": {
      "frame": "#78878f",
      "tab_background_text": "#1b2738"
    }
  },
  "version": "2.0",
  "name": "Halloween Jack Night ...",
  "manifest_version": 2,
  "description": "Black Cat,Haunted Castle,Spider,\nFunny pumpkins, Witch and her broom,Mouse, Cat, Chat Noir,Cauldron,Ghosts,Moon,Night,\nBlack,Dark,Evening,Town,City,\nSkyline,Thunderstorm, Flashes of Lighting Lantern...\nHappy Happy Halloween..."
}