Examine source code of Darktech_persona

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#ff7b00",
      "tab_background_text": "#c7cdd6"
    }
  },
  "version": "2.0",
  "name": "Darktech_persona",
  "manifest_version": 2,
  "description": "Dark Firefox/Thunderbird theme\n\nChangelog. 22.1.2014: Font color updated to white so that theme would be clearer to use."
}