Examine source code of green sing

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "sing green",
  "theme": {
    "images": {},
    "properties": {},
    "colors": {
      "toolbar": "rgb(230, 240, 206)",
      "toolbar_text": "rgb(1, 2, 3)",
      "frame": "rgb(230, 240, 206)",
      "tab_background_text": "rgb(0, 0, 0)",
      "toolbar_field": "rgb(255, 255, 255)",
      "toolbar_field_text": "rgb(88, 128, 159)",
      "tab_line": "rgb(138, 169, 106)",
      "popup": "rgb(230, 240, 206)",
      "popup_text": "rgb(0, 0, 0)",
      "tab_loading": "rgb(138, 169, 106)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{f42c8ce2-29eb-404e-b325-b26687d575c0}"
    }
  }
}