Examine source code of TARDIS Blue

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#5499e3",
      "tab_background_text": "#4c91e0"
    }
  },
  "version": "2.0",
  "name": "TARDIS Blue",
  "manifest_version": 2,
  "description": "The Doctor's TARDIS has the best subwave scanners and wi-fi browsers known to the universe - so why not mimic it with this TARDIS person for Mozilla Firefox?"
}