Examine source code of ENT ++ (dark theme)

{
  "manifest_version": 2,
  "name": "ENT++",
  "version": "0.1",
  "description": "ENT ++",
  "icons": {
    "48": "icon.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.ecollege.haute-garonne.fr/*"
      ],
      "js": [
        "ent.js"
      ]
    }
  ],
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "icon.png",
    "default_title": "ENT ++"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{e691a4bd-f3d9-4ecc-bcd8-ba529b575435}"
    }
  }
}