Examine source code of Refined Medium

{
  "manifest_version": 2,
  "name": "Refined Medium",
  "version": "0.0.5resigned1",
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "on.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "run_at": "document_end",
      "js": [
        "content.js"
      ]
    }
  ],
  "web_accessible_resources": [
    "styles.css"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{304bbce4-7041-4157-ad54-b9a59f2dcc07}"
    }
  }
}