Examine source code of Mint Green Butterfly

{
  "name": "Green Butterfly",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "Firefox_Theme_Butterfly.png"
    },
    "colors": {
      "frame": "rgba(255, 255, 255, 1)",
      "tab_background_text": "rgba(0, 0, 0, 1)",
      "toolbar": "rgba(192, 255, 160, 0.7)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(0, 255, 0, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{0757d11a-bd4b-4329-ba87-ca9e83ea46b4}"
    }
  }
}