Examine source code of Gruvbox style

{
  "name": "Gruvbox style",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "Firefoxthemebg.png"
    },
    "colors": {
      "frame": "rgba(40, 40, 40, 1)",
      "tab_background_text": "rgba(235, 219, 178, 1)",
      "toolbar": "rgba(29, 32, 33, 1)",
      "bookmark_text": "rgba(235, 219, 178, 1)",
      "toolbar_field": "rgba(80, 73, 69, 1)",
      "toolbar_field_text": "rgba(235, 219, 178, 1)",
      "tab_line": "rgba(168, 153, 132, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{2660a05b-4f2a-4876-a412-7e1290ab5a73}"
    }
  }
}