Examine source code of Springtime it is here

{
  "theme": {
    "images": {
      "theme_frame": "springtimeitshere.JPG"
    },
    "colors": {
      "frame": "#175cb0",
      "tab_background_text": "#24105c"
    }
  },
  "version": "2.0",
  "name": "Springtime it is here",
  "manifest_version": 2,
  "description": "In springtime birds is so happy."
}