Examine source code of Textise-it

{
  "author": "Carlos Cuenca",
  "manifest_version": 2,
  "name": "Textise it",
  "version": "0.9.26",
  "description": "__MSG_extensionDescription__",
  "icons": {
    "40": "icons/40/app.png",
    "48": "icons/48/app.png",
    "128": "icons/128/app.png"
  },
  "applications": {
    "gecko": {
      "strict_min_version": "52.0"
    }
  },
  "default_locale": "en",
  "developer": {
    "name": "ProtheusDK"
  },
  "browser_action": {
    "default_icon": {
      "40": "icons/40/app.png",
      "48": "icons/48/app.png",
      "128": "icons/128/app.png"
    },
    "default_title": "__MSG_menuTitle__"
  },
  "incognito": "spanning",
  "permissions": [
    "<all_urls>",
    "activeTab",
    "tabs"
  ],
  "background": {
    "scripts": [
      "app.js"
    ],
    "persistent": true
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content_scripts/content.js"
      ],
      "run_at": "document_end",
      "all_frames": true
    }
  ]
}