Examine source code of Dark Matte Texture

{
  "name": "Dark Matte Texture",
  "manifest_version": 2,
  "version": "2.0",
  "theme": {
    "images": {
      "theme_frame": "header2.png"
    },
    "colors": {
      "frame": "rgba(27, 29, 34, 1)",
      "tab_background_text": "rgba(141, 142, 145, 1)",
      "toolbar": "rgba(50, 52, 58, 1)",
      "bookmark_text": "rgba(189, 191, 193, 1)",
      "toolbar_field": "rgba(32, 34, 39, 1)",
      "toolbar_field_text": "rgba(141, 142, 145, 1)",
      "tab_line": "rgba(54, 54, 65, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{3308ea09-5238-48ae-9bb7-1c8fb35dff1d}"
    }
  }
}