Examine source code of Edge - Wandering Fields

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Edge - Wandering Fields",
  "theme": {
    "images": {},
    "properties": {},
    "colors": {
      "toolbar": "rgb(62, 100, 129)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(17, 57, 80)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(255, 255, 255)",
      "toolbar_field_text": "rgb(102, 102, 102)",
      "tab_line": "rgb(255, 255, 255)",
      "popup": "rgb(255, 255, 255)",
      "popup_text": "rgb(102, 102, 102)",
      "button_background_active": "rgb(77, 112, 139)",
      "button_background_hover": "rgb(77, 112, 139)",
      "tab_loading": "rgb(255, 255, 255)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{7577ef9f-9384-446f-a7ee-929a2be4c62f}"
    }
  }
}