Examine source code of Black-Grid

{
  "name": "Black-Grid",
  "manifest_version": 2,
  "version": "12.0",
  "theme": {
    "images": {
      "theme_frame": "grade1.png"
    },
    "colors": {
      "frame": "rgba(20, 20, 20, 0.9)",
      "tab_background_text": "rgba(140, 255, 0, 1)",
      "toolbar": "rgba(82, 82, 82, 0.3)",
      "bookmark_text": "rgba(140, 255, 0, 1)",
      "toolbar_field": "rgba(15, 15, 15, 0.6)",
      "toolbar_field_text": "rgba(136, 255, 0, 0.9)",
      "tab_line": "rgba(136, 255, 0, 0.3)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{e1ce1712-1121-4fc1-82a5-107affe323ba}"
    }
  }
}