Examine source code of Individual window themes

{
  "manifest_version": 2,
  "name": "Individual window themes",
  "version": "1.1",
  "description": "Set the colour of each window separately",
  "homepage_url": "https://github.com/chronakis/firefox-window-theme",
  "icons": {
    "128": "icon.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "permissions": [
    "tabs",
    "theme",
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{441809e6-c885-4461-a13c-804df54033f9}"
    }
  }
}