Examine source code of blue one

{
  "theme": {
    "images": {
      "theme_frame": "1.JPG"
    },
    "colors": {
      "frame": "#353985",
      "tab_background_text": "#eff2f7"
    }
  },
  "version": "2.0",
  "name": "blue one",
  "manifest_version": 2
}