Examine source code of eBreak

{
  "manifest_version": 2,
  "name": "eBreak",
  "version": "1.7",
  "description": "Auto calculation of break time in eGecko",
  "permissions": [
    "activeTab",
    "storage"
  ],
  "browser_action": {
    "default_icon": {
      "16": "icons/icon-off-16.png",
      "32": "icons/icon-off-32.png",
      "48": "icons/icon-off-48.png",
      "128": "icons/icon-off-128.png"
    },
    "default_popup": "popup.html"
  },
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{9d512393-6113-4924-aa31-3c4a3b0b18c3}"
    }
  }
}